<PAGE>

                      AMENDMENT TO STOCK PURCHASE AGREEMENT

THIS AMENDMENT TO STOCK PURCHASE AGREEMENT ("this Amendment") is entered into as
of April 16, 1998, by and among Econophone, Inc., a New York corporation
("Buyer"); and Richard Masino, an individual domiciliary of the State of New
York ("Masino"), and Robert Wunder, an individual domiciliary of the State of
Connecticut ("Wunder"), together the former holders of all the issued and
outstanding shares of capital stock of VoiceNet Corporation, a New York
corporation ("the Company") (each of Masino and Wunder individually a "Seller"
and together, jointly and severally, the "Sellers").

                                    RECITALS

         The parties previously have entered into a Stock Purchase Agreement
dated as of January 28, 1998 ("the Agreement").

         The parties mutually desire to amend the Agreement in certain respects,
and to restate and reconfirm the remaining unperformed terms and conditions of
the Agreement that are not amended hereby.

         Now, therefore, in consideration of the foregoing covenants and
promises, and other good and valuable consideration, the parties agree as
follows:

         1. All defined terms in the Agreement shall have the same meanings in
this Amendment, unless otherwise specified.

         2. Section 3.1 of the Agreement is hereby deleted in its entirety and
the following text is substituted in place of the deleted provisions:

         3.1      The Purchase Price payable in respect of the Shares shall be
                  increased by an amount (the "Earn-Out Bonus"), calculated and
                  paid as follows:

                  3.1.1    DURING THE PERIOD FROM AND INCLUDING APRIL 16, 1998
                           TO AND INCLUDING APRIL 15, 1999: the Earn-Out Bonus
                           shall be calculated on two components, computed over
                           the period from and including the 16th of each
                           calendar month to and including the 15th of the
                           following calendar month: (A) 4.08% of Base Year
                           Calling Card Revenues (as defined below), plus (B)
                           1.2% of Base Year Additional Revenues (as defined
                           below); PROVIDED, that no single element of Earn-Out
                           Bonus will be calculated on both of the separate
                           components specified in this subsection. For all
                           purposes of this subsection 3.1.1, the following
                           definitions shall apply:


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                           (w) "Base Year Calling Card Revenues" shall mean that
                           amount by which Net Monthly Revenues ("NMR", as
                           defined below) of Calling Card Services (defined
                           below) shall exceed US$3,500,000;

                           (x) "Base Year Additional Revenues" shall mean the
                           combined NMR of postpaid "1+", prepaid "1+", fixed
                           termination toll-free "800"/"888", reroutable
                           toll-free "800"/ "888", ITFS, and local access PIN
                           services generated by the VoiceNet business unit of
                           Econophone (collectively, the "Other Services"),
                           calculated upon the full US dollar increment above a
                           base of zero;

                           (y) "NMR" shall mean the gross monthly revenues of
                           Calling Card Services or Other Services, as the case
                           may be, generated by the VoiceNet business unit of
                           Econophone, but shall not include (a) universal
                           service charges and other access fees, payphone
                           surcharges and other surcharges, directory assistance
                           charges, line and installation charges, monthly fees,
                           taxes, promotional discounts, minimum usage charges,
                           fraudulent charges, or subsequently credited charges
                           for any of the foregoing, or (b) those revenues for
                           which Sellers or their Affiliates otherwise receive
                           commissions pursuant to separate agreements or
                           arrangements;

                           (z) "Calling Card Services" shall mean the following
                           calling card products and services only, and no other
                           products or services: (a) postpaid calling card
                           products and postpaid calling card services marketed
                           by the VoiceNet business unit of Econophone
                           (excluding postpaid calling card products and
                           services marketed by Econophone independently of the
                           VoiceNet business unit, other than those products or
                           services that were developed by the VoiceNet business
                           unit) and (b) prepaid calling card products and
                           prepaid calling card services marketed by the
                           VoiceNet business unit of Econophone (excluding
                           prepaid calling card products and services marketed
                           by Econophone independently of the VoiceNet business
                           unit, other than those products or services that were
                           developed by the VoiceNet business unit).

                  3.1.2    DURING THE PERIOD FROM AND INCLUDING APRIL 16, 1999
                           TO AND INCLUDING APRIL 15, 2000: the Earn-Out Bonus
                           shall be calculated on two components, computed over
                           the period from and including the 16th of each
                           calendar month to and including the 15th of the
                           following calendar month: (A) 2.5% of Second Year
                           Calling Card Revenues (as defined below), plus (B)
                           1.2% of Second Year 


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                           Additional Revenues (as defined below); provided,
                           that no single element of Commission will be
                           calculated on both of the separate components
                           specified in this subsection. For all purposes of
                           this subsection 3.1.2, the following definitions
                           shall apply:

                           (w) "Second Year Calling Card Revenues" shall mean
                           that amount by which NMR of Calling Card Services
                           during the applicable month shall exceed the average
                           NMR of Calling Card Services for the three-month
                           period from and including January 16, 1999 through
                           and including April 15, 1999;

                           (x) "Second Year Additional Revenues" shall mean the
                           amount by which the combined NMR of Other Services
                           shall exceed the average combined NMR of Other
                           Services for the three-month period January 16, 1999
                           through April 15, 1999.

                  3.1.3    DURING THE PERIOD FROM AND INCLUDING APRIL 16, 2000
                           TO AND INCLUDING APRIL 15, 2001: the Commission shall
                           be calculated on two components, computed over the
                           period from and including the 16th of each calendar
                           month to and including the 15th of the following
                           calendar month: (A) 2.5% of Third Year Calling Card
                           Revenues (as defined below), plus (B) 1.2% of Third
                           Year Additional Revenues (as defined below);
                           provided, that no single element of Commission will
                           be calculated on both of the separate components
                           specified in this subsection. For all purposes of
                           this subsection 3.1.3, the following definitions
                           shall apply:

                           (w) "Third Year Calling Card Revenues" shall mean
                           that amount by which NMR of Calling Card Services
                           shall exceed the average of the actual monthly
                           revenues for the three-month period from and
                           including January 16, 2000 through and including
                           April 15, 2001;

                           (x) "Third Year Additional Revenues" shall mean the
                           amount by which the combined NMR of Other Services
                           shall exceed the average of the combined NMR of Other
                           Services for the three-month period from and
                           including January 16, 2000 through and including
                           April 15, 2001.

                  3.1.4    The actual amount of each monthly payment of Earn-Out
                           Bonus shall be the figure determined in accordance
                           subsection 3.1.1, 3.1.2 or 3.1.3 hereof, as the case
                           may be, less $15,000.

                  3.1.5    In the event that the Employment Agreements (as
                           defined in subsection 5.1.6 below) are terminated
                           pursuant to paragraphs (a), 


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                           (b) or (c) of Section 8 thereof, any Earn-Out-Bonus
                           theretofore accrued but not paid up to the date of
                           such termination shall be due and payable in
                           accordance with the terms of subsection 3.2.1 of this
                           Agreement.

         3. Section 3.2.1 of the Agreement is hereby deleted in its entirety and
the following text is substituted in place of the deleted provision:

                  3.2.1    The Earn-Out Bonus shall be computed and paid by
                           Econophone no later than the 10th day following the
                           conclusion of any billing cycle (currently the 15th
                           day of each calendar month) with respect to the
                           immediately preceding concluded billing cycle, and
                           shall be payable with respect to all complete billing
                           cycles (and on a pro rata basis for any partial
                           billing cycle) for so long as both Employment
                           Agreements (as defined in subsection 5.1.6 below)
                           continue in effect; PROVIDED, HOWEVER, that in the
                           event either Employment Agreement is terminated
                           pursuant to Section 8(d) thereof, with the effect
                           that no further Earn-Out Bonus shall be payable on
                           account of such termination, then Sellers shall be
                           entitled to a single final payment equal to the
                           amount (if any) by which the average of the last
                           three cycle payments of Earn-Out Bonus prior to the
                           termination exceeds six months' salary payable
                           pursuant to Section 8(d) of the Employment Agreement.

         4. The Employment Agreements dated February 12, 1998, referenced in
Subsection 5.1.6 of the Agreement and annexed to the Agreement as Exhibits A-1
and A-2 are hereby terminated and shall be of no further force and effect. Each
of Sellers has entered into a replacement Employment Agreement dated as of the
same date as this Amendment, copies of which are annexed hereto as Exhibits A-1
and A-2, and all references in the Agreement to either or both of the Employment
Agreements shall hereafter mean the replacement Employment Agreements described
herein in this Paragraph 3.

         5. All others terms and conditions of the Agreement shall remain in
full force and effect. In the event of any ambiguity between the provisions of
this Amendment and the language of the Agreement, the provisions of this
Amendment shall control.


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         IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed as of the date first written above.


SELLERS:                            BUYER:


RICHARD MASINO                      ECONOPHONE, INC.


________________________________    By: ________________________________


ROBERT WUNDER                       Name: ______________________________


________________________________    Title: _______________________________


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                                                                     EXHIBIT A-1

                           WUNDER EMPLOYMENT AGREEMENT


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                                                                     EXHIBIT A-2

                           MASINO EMPLOYMENT AGREEMENT


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