AMENDMENT, WAIVER, RESIGNATION AND APPOINTMENT AGREEMENT

Exhibit 10.1

Execution Copy

AMENDMENT, WAIVER, RESIGNATION AND

APPOINTMENT AGREEMENT

THIS AMENDMENT, WAIVER, RESIGNATION AND APPOINTMENT AGREEMENT, dated as of May 4, 2009 (this “ Amendment ”), is by and among SYNIVERSE HOLDINGS, INC. , a Delaware corporation (the “ Parent ”), SYNIVERSE TECHNOLOGIES, INC. , a Delaware corporation (the “ Borrower ”), the Lenders (as defined below) party hereto, LEHMAN COMMERCIAL PAPER INC. (“ LCPI ”), a debtor and debtor in possession under chapter 11 of the Bankruptcy Code (as defined below), as resigning Administrative Agent (as each such role is defined in the 2007 Credit Agreement defined below and in the other Loan Documents) and Swing Line Lender under the 2007 Credit Agreement (as defined below), and BANK OF AMERICA, N.A. (“ Bank of America ”), as successor Administrative Agent and Swing Line Lender under the Amended Credit Agreement (as defined below).

W I T N E S S E T H:

WHEREAS , the Borrower is party to that certain Amended and Restated Credit Agreement, dated as of August 9, 2007 (as amended, restated or otherwise modified to but excluding the Effective Date (as defined below) hereof, the “ 2007 Credit Agreement ”), among the Parent, the Borrower, the financial institutions from time to time party thereto, as lenders (collectively, the “ Lenders ” and each a “ Lender ”), Lehman Brothers Inc. and Deutsche Bank Securities Inc., as joint lead arrangers and joint book-running managers, Lehman Commercial Paper Inc. (“ LCPI ”), as administrative agent and collateral agent (in such capacity, the “ Administrative Agent ”), Deutsche Bank AG New York Branch, as syndication agent (the “ Syndication Agent ”), and Bear Stearns Corporate Lending Inc. and LaSalle Bank National Association, as co-documentation agents (together with the Administrative Agent and the Syndication Agent, collectively, the “ Agents ”); capitalized terms used and not otherwise defined herein shall have the meanings assigned to such terms in the 2007 Credit Agreement;

WHEREAS , on October 5, 2008, LCPI commenced a voluntary case under chapter 11 of title 11 of the United States Code (the “ Bankruptcy Code ”) and on such date, pursuant to section 362(a) of the Bankruptcy Code, an automatic stay went into effect that prohibits actions to interfere with, or obtain possession or control of, LCPI’s property or to collect or recover from LCPI any debts or claims that arose before such date;

WHEREAS , on October 6, 2008, the United States Bankruptcy Court for the Southern District of New York entered an order (the “ Bankruptcy Court Order ”) in the bankruptcy case of LCPI authorizing and empowering LCPI to transfer, assign or resign from any administrative agent positions in LCPI’s business judgment in accordance with the provisions of any applicable credit agreements and in accordance with the Bankruptcy Court Order; and

WHEREAS , the Borrower has notified the Lenders, pursuant to the notice attached as Exhibit A hereto (the “ Notice ”), that (a) LCPI desires to resign as Administrative Agent and Swing Line Lender under the Loan Documents and (b) Bank of America has agreed to be appointed as successor Administrative Agent and Swing Line Lender under the Loan

Documents, in each case in accordance with (i) Section 9.9 of the 2007 Credit Agreement, (ii) the Resignation, Assignment and Assumption Agreement, substantially in the form of Exhibit B attached hereto (the “ Assignment and Assumption ”), and (iii) the terms and conditions hereof;

NOW THEREFORE , for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

SECTION 1.01. Amendments to Section 1 . Section 1.1 of the 2007 Credit Agreement is hereby amended, effective as of the Effective Date, by:

(a) deleting the definitions of Base Rate, Business Day, Defaulting Lender, Dollar Equivalent, Euribor Base Rate, Euribo Rate, Eurocurrency Base Rate, Eurocurrency Loans, Eurocurrency Reserve Requirements and Federal Funds Effective Rate, and inserting the following definitions in alphabetical order:

“ Agent Parties ”: as defined in Section 10.2(c).

“ Bank of America ”: Bank of America, N.A.

“ Bankruptcy Code ”: chapter 11 of title 11 of the United States Code.

“ Base Rate ”: for any day a fluctuating rate per annum equal to the highest of (a) the Federal Funds Effective Rate plus  ¹ / 2 of 1.00%, (b) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its “prime rate” and (c) the 30-day Eurocurrency Rate for Dollars plus 1.00% The “prime rate” is a rate set by Bank of America, based upon various factors including Bank of America’s costs and desired return, general economic conditions and other factors, and is used as a reference point for pricing some loans, which may be priced at, above, or below such announced rate. Any change in such rate announced by Bank of America shall take effect at the opening of business on the day specified in the public announcement of such change.

“ BBA LIBOR ”: as specified in the definition of Eurocurrency Rate.

“ Borrower Materials ”: as defined in Section 10.2(c).

“ Business Day ”: any day other than a Saturday, Sunday or other day on which commercial banks are authorized to close under the Laws of, or are in fact closed in, the state where the Administrative Agent’s Office with respect to Obligations denominated in Dollars is located and:

(a) if such day relates to any interest rate settings as to a Eurocurrency Loan denominated in Dollars, any fundings, disbursements, settlements and payments in Dollars in respect of any such Eurocurrency Loan, or any other dealings in Dollars to be carried out pursuant to this Agreement in respect of any such Eurocurrency Loan, means any such day on which dealings in deposits in Dollars are conducted by and between banks in the London interbank eurodollar market; and

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(b) if such day relates to any interest rate settings as to a Eurocurrency Loan denominated in Euro, any fundings, disbursements, settlements and payments in Euro in respect of any such Eurocurrency Loan, or any other dealings in Euro to be carried out pursuant to this Agreement in respect of any such Eurocurrency Loan, means a TARGET Day.

“ Defaulting Lender ”: any Lender (a) that has failed to fund any portion of its Revolving Commitment, its obligations under Section 2.26 , its obligations as a Multicurrency L/C Participant or participations in Swing Line Loans required to be funded by it hereunder within one Business Day of the date required to be funded by it hereunder unless such failure has been cured, (b) that has otherwise failed to pay over to the Administrative Agent, any Multicurrency Issuing Lender or any other Lender any other amount required to be paid by it hereunder within one Business Day of the date when due, unless the subject of a good faith dispute or unless such failure has been cured, or (c) with respect to which a Distress Event has occurred (or has occurred with respect to any Affiliate of such Lender that directly or indirectly controls such Lender) and has not been cured in accordance with Section 10.24 .

“ Distress Event ”: with respect to any Person (each, a “ Distressed Person ”), a voluntary or involuntary case with respect to such Distressed Person under the Bankruptcy Code or any similar bankruptcy laws of its jurisdiction of formation, or a custodian, conservator, receiver or similar official is appointed for such Distressed Person or any substantial part of such Distressed Person’s assets, or such Distressed Person makes a general assignment for the benefit of creditors or is otherwise adjudicated as, or determined by any governmental authority having regulatory authority over such Distressed Person or its assets to be, insolvent, bankrupt, or deficient in meeting any capital adequacy or liquidity standard of any governmental authority applicable to such Distressed Person.

“ Dollar Equivalent ”: at any time, (a) with respect to any amount denominated in Dollars, such amount, and (b) with respect to any amount denominated in Euros, the equivalent amount thereof in Dollars as determined by the Administrative Agent or the Multicurrency Issuing Lender, as the case may be, at such time on the date of determination on the basis of the Spot Rate for the purchase of Dollars with Euros as of such date.

“ Distressed Person ”: as specified in the definition of Distress Event.

“ Euribo Rate ”: as of any date of determination, the Eurocurrency Rate for such date for any Loan denominated in Euros.

“ Eurocurrency Base Rate ”: as specified in the definition of Eurocurrency Rate.

“ Eurocurrency Loans ”: Loans for which the applicable rate of interest is based upon the Eurocurrency Rate (excluding Loans for which the applicable rate of interest is based on clause (c) of the definition of Base Rate) or Euribo Rate.

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“ Eurocurrency Rate ”: for any Interest Period with respect to a Eurocurrency Loan, a rate per annum determined by the Administrative Agent pursuant to the following formula:

Where, “ Eurocurrency Base Rate ” means, for such Interest Period:

(a) the rate per annum equal to the British Banker’s Association LIBOR Rate (“ BBA LIBOR ”), as published by Reuters (or other commercially available source providing quotations of BBA LIBOR as designated by the Administrative Agent from time to time) at approximately 11:00 a.m., London time, two Business Days prior to the commencement of such Interest Period, for deposits in the relevant currency (for delivery on the first day of such Interest Period) with a term equivalent to such Interest Period.

(b) If such rate referenced in the preceding clause (a) is not available at such time for any reason, then the “ Eurocurrency Base Rate ”) for such Interest Period shall be the rate per annum determined by the Administrative Agent to be the rate at which deposits in the relevant currency for delivery on the first day of such Interest Period in Same Day Funds in the approximate amount of the Eurocurrency Loan being made, continued or converted by Bank of America and with a term equivalent to such Interest Period would be offered by Bank of America’s London Branch (or other Bank of America branch or Affiliate) to major banks in the London or other offshore interbank market for such currency at their request at approximately 11:00 a.m. (London time) two Business Days prior to the commencement of such Interest Period.

“ Eurocurrency Reserve Requirements ”: for any day during any Interest Period, the reserve percentage (expressed as a decimal, carried out to five decimal places) in effect on such day, whether or not applicable to any Lender, under regulations issued from time to time by the FRB for determining the maximum reserve requirement (including any emergency, supplemental or other marginal reserve requirement) with respect to Eurocurrency funding (currently referred to as “Eurocurrency liabilities”). The Eurocurrency Rate for each outstanding Eurocurrency Loan shall be adjusted automatically as of the effective date of any change in the Eurocurrency Reserve Requirements.

“ Euro Equivalent ”: at any time, (a) with respect to any amount denominated in Euros, such amount, and (b) with respect to any amount expressed in Dollars, the equivalent amount thereof in Euros as determined by the

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Administrative Agent or the Multicurrency Issuing Lender, as the case may be, at such time on the basis of the Spot Rate on the date of determination for the purchase of Euros with Dollars as of such date.

“ Federal Funds Effective Rate ”: for any day, the rate per annum equal to the weighted average of the rates on overnight Federal funds transactions with members of the Federal Reserve System arranged by Federal funds brokers on such day, as published by the Federal Reserve Bank of New York on the Business Day next succeeding such day; provided that (a) if such day is not a Business Day, the Federal Funds Effective Rate for such day shall be such rate on such transactions on the next preceding Business Day as so published on the next succeeding Business Day, and (b) if no such rate is so published on such next succeeding Business Day, the Federal Funds Effective Rate for such day shall be the average rate (rounded upward, if necessary, to a whole multiple of  ¹ / 100 of 1%) charged to Bank of America, on such day on such transactions as determined by the Administrative Agent.

“ First Amendment ” means that certain Amendment, Waiver, Resignation and Appointment Agreement, dated as of May 4, 2009, among the Parent, the Borrower, Lehman Commercial Paper Inc., as resigning Administrative Agent, Bank of America, N.A., as replacement Administrative Agent and the Required Lenders party thereto.

“ First Amendment Effective Date ” means the “Effective Date” as defined in the First Amendment.

“ FRB ”: the Board of Governors of the Federal Reserve System of the United States.

“ Impacted Lender ”: any Revolving Credit Lender (a) that has given verbal or written notice to the Administrative Agent or any Lender or has otherwise publicly announced that such Lender believes it will become, or that fails following inquiry promptly to provide to the Administrative Agent, a Multicurrency Issuing Lender or the Swing Line Lender making such inquiry reasonably satisfactory assurance that such Lender will not become, a Defaulting Lender, or (b) as to which the Administrative Agent or a Multicurrency Issuing Lender has a good faith belief that such Lender has defaulted more than once in fulfilling its funding obligations (as a lender, letter of credit issuer or issuer of bank guarantees and including, but not limited to, funding or paying when due loan requests, swingline participations, letter of credit participations, pro rata sharing obligations and expense and indemnification obligations) under any other syndicated credit facility and such Lender shall not have provided assurances satisfactory to the Administrative Agent and Multicurrency Issuing Lender that despite such defaults such Lender will not become a Defaulting Lender hereunder.

“ Laws ”: collectively, all international, foreign, Federal, state and local statutes, treaties, rules, guidelines, regulations, ordinances, codes and

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administrative or judicial precedents or authorities, including the interpretation or administration thereof by any Governmental Authority charged with the enforcement, interpretation or administration thereof, and all applicable administrative orders, directed duties, requests, licenses, authorizations and permits of, and agreements with, any Governmental Authority, in each case whether or not having the force of law.

“ Lender Cure Period ”: as defined in Section 10.24.

“ Platform ”: as defined in Section 10.2(c).

“ Public Lender ”: as defined in Section 10.2(c).

“ Reinstatement Date ”: as defined in Section 10.24.

“ Same Day Funds ”: (a) with respect to disbursements and payments in Dollars, immediately available funds, and (b) with respect to disbursements and payments in Euros, same day or other funds as may be determined by the Administrative Agent or the Multicurrency Issuing Lender, as the case may be, to be customary in the place of disbursement or payment for the settlement of international banking transactions in Euros.

“ Specified Lender Default ”: as defined in Section 10.24.

“ Spot Rate ”: for a currency means the rate determined by the Administrative Agent or the Multicurrency Issuing Lender, as applicable, to be the rate quoted by the Person acting in such capacity as the spot rate for the purchase by such Person of such currency with another currency through its principal foreign exchange trading office at approximately 11:00 a.m. on the date two Business Days prior to the date as of which the foreign exchange computation is made; provided that the Administrative Agent or the Multicurrency Issuing Lender may obtain such spot rate from another financial institution designated by the Administrative Agent or the Multicurrency Issuing Lender if the Person acting in such capacity does not have as of the date of determination a spot buying rate for any such currency; and provided further that the Multicurrency Issuing Lender may use such spot rate quoted on the date as of which the foreign exchange computation is made in the case of any Multicurrency Letter of Credit.

“ TARGET Day ”: any day on which the Trans-European Automated Real-time Gross Settlement Express Transfer (TARGET) payment system (or, if such payment system ceases to be operative, such other payment system (if any) determined by the Administrative Agent to be a suitable replacement) is open for the settlement of payments in Euro.

(b) inserting the following proviso immediately before the “.” at the end of the definition of “ Majority Facility Lenders ”:

“; provided that, in any event, the Commitment of, and the portion of the Commitment outstanding held or deemed held by, any Defaulting Lender shall be excluded for purposes of making a determination of Majority Facility Lenders.”

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(c) inserting the following proviso immediately before the “.” at the end of the definition of “ Required Lenders ”:

“; provided that, in any event, the Commitment of, and the portion of the Commitment outstanding held or deemed held by, any Defaulting Lender shall be excluded for purposes of making a determination of Required Lenders.”

SECTION 1.02. Replacement of References to LCPI . Other than in the first recital of the 2007 Credit Agreement, each instance of the words “Lehman Commercial Paper Inc.” is hereby replaced with “Bank of America, N.A.” and “LCPI” in the 2007 Credit Agreement is hereby replaced with “Bank of America”.

SECTION 1.03. Termination of LCPI Revolving Credit Commitment; Incremental Revolving Credit Commitment

(a) In accordance with Section 10.1(a)(viii) of the 2007 Credit Agreement, each Revolving Credit Lender hereby waives the requirement of Section 2.18(a) of the 2007 Credit Agreement that any reduction in the Revolving Credit Commitments be made pro rata and each such Revolving Credit Lender, together with the Borrower and each other undersigned Lender, hereby consents, effective as of the Effective Date, to the termination of 100% of the Revolving Credit Commitments of LCPI, it being understood that the aggregate outstanding amount of the Revolving Credit Loans as of the date hereof is zero ($0). In furtherance thereof, it is hereby agreed that upon such termination of LCPI as a Revolving Credit Lender, the Revolving Credit Percentage, the Revolving Credit Dollar Percentage and the Revolving Credit Euro Percentage of LCPI automatically shall be reduced to zero percent (0%) and the applicable Revolving Credit Percentage, the Revolving Credit Dollar Percentage and the Revolving Credit Euro Percentage of each other Revolving Credit Lender shall be increased such that the Revolving Credit Percentage, the Revolving Credit Dollar Percentage and the Revolving Credit Euro Percentage of all the remaining Revolving Credit Lenders equals one hundred percent (100%) respectively. Concurrently with any subsequent payment of interest or fees to the Lenders with respect to any period before the foregoing termination of Revolving Credit Commitments, the Borrower shall pay to the Administrative Agent, for the account of LCPI, LCPI’s ratable share (based on its Revolving Credit Commitments before giving effect to such termination) of such interest or fees, as applicable. From and after the Effective Date, LCPI shall have no further obligation to fund any amount or extend any credit under the Loan Documents.

(b) Subject to the occurrence of the Effective Date with respect to this Amendment, the Borrower hereby exercises its rights under Section 2.26(a) of the Amended Credit Agreement to request, and Bank of America, N.A., in its capacity as a Revolving Credit Lender, hereby agrees, effective as of the Effective Date hereof (which date shall constitute the Incremental Effective Date with respect to such increase) to accept the Borrower’s allocation of, a $10,000,000 Incremental Revolving Credit Commitment.

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SECTION 1.04. Amendments to Section 2 .

(a) Section 2.5 of the 2007 Credit Agreement is hereby amended by inserting “(or, if Swing Line Loans are unavailable for any reason other than failure to satisfy conditions precedent set forth in Section 5.3, prior to 1:00 PM, New York City time)” immediately after “prior to 12:00 Noon, New York City time” in the first sentence thereof.

(b) Section 2.6 of the 2007 Credit Agreement is hereby amended by inserting “, at its sole discretion,” immediately after “the Swing Line Lender agrees” in the second line thereof.

(c) The first sentence of Section 2.16(a) of the 2007 Credit Agreement is hereby deleted in its entirety and replaced with the following:

Interest, fees and commissions payable pursuant hereto shall be calculated on the basis of a 360-day year for the actual days elapsed, except that, with respect to the calculation of Base Rate Loans, the interest thereon shall be calculated on the basis of a  ³⁶⁵ / 366 -day year for the actual days elapsed.

(d) Clause (ii) of Section 2.24(a) of the 2007 Credit Agreement is hereby deleted in its entirety and replaced with the following: “(ii) any Lender is a Defaulting Lender”.

(e) The first sentence of Section 2.26(a) of the 2007 Credit Agreement is hereby deleted in its entirety and replaced with the following:

The Borrower may request, at any time prior to the date that is one hundred eighty (180) days prior to the Term Loan Maturity Date (with respect to incremental Term Loans) or one hundred eighty (180) days prior to the Revolving Credit Termination Date (with respect to an increase in the Revolving Credit Commitments), by irrevocable written notice to the Administrative Agent, (i) an increase in the existing Revolving Credit Commitments (any such increase, an “ Incremental Revolving Credit Commitment ”) in an amount not in excess of $130,000,000 in the aggregate and not less than $10,000,000 individually or (ii) incremental term loans (each, an “ Incremental Term Loan ”) in an amount not in excess of $100,000,000 in the aggregate and not less than $25,000,000 individually; provided , that in no event shall the aggregate amount of all Incremental Revolving Credit Commitments and Incremental Term Loans exceed $130,000,000.

SECTION 1.05. Amendments to Section 3 .

(a) Section 3.1(a) of the 2007 Credit Agreement is hereby amended by inserting the following at the end thereof:

Notwithstanding the foregoing, in the event that (i) a Lender is a Defaulting Lender or (ii) any Multicurrency Issuing Lender determines in good faith or obtains actual knowledge that any Lender is an Impacted Lender (in which case such Multicurrency Issuing Lender shall give prompt notice thereof to the

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Borrower and the Administrative Agent), the respective Multicurrency Issuing Lender shall not be required to issue any Multicurrency Letter of Credit unless arrangements satisfactory to the respective Multicurrency Issuing Lender shall have been entered into to eliminate such Multicurrency Issuing Lender’s risk