"Phone.coms Interoperability Lab demonstrates our commitment to rapid rollout of interoperable WAP solutions. It will speed time-to-market for all vendors who want to ensure that they offer 100% WAP compatible, stress-tested products in a complex, multi-vendor environment," states Chuck Parrish, executive vice president of Phone.com and vice chairman of the WAP Forum. "This is a major step forward for the wireless Internet industry."

Phone.coms Interoperability Lab has been conducting tests with major European handset manufacturers as well as WAP gateway manufacturers and has successfully proven that close cooperation between multiple vendors and their customers is a win-win for all involved.

In order to participate in the Interoperability Lab, Phone.com requires that the product manufacturer describe the desired device and gateway tests by completing an Interoperability Testing Form, available April 5, 2000 from Phone.com, and that the company book testing time at The lab in advance. Staff at the lab will be on hand to help with the testing procedures and facilities. Fees will be scaled to cover the testing time and materials used.

Background:
Phone.coms commitment to interoperability with other vendors spans its entire product line including the gateways, browsers and applications. Phone.com has already signed Memorandums of Understanding and does ongoing interoperability testing with major handset manufacturers. . Phone.coms commitment to the WAP Forum and the WAP Standard has lead them to chair the Interoperability and Testing Executive Committee of the WAP Forum and to actively support the Working Interoperability Group. Phone.com works closely with its carrier customers to ensure interoperability and is working to deliver authoring guidelines to ensure that developers can build applications that scale across multiple devices.

To deliver interoperability, the WAP Forum has defined and delivered a standard protocol that is scalable across a range of devices. This standard, WAP 1.1, is intended to ensure interoperability. To enable vendors to comply with WAP 1.1, the WAP Forum has contracted The Open Group, an independent certification authority, to deliver a certification test that will cover all parts of the wireless Internet solution, including gateways, browsers, and content by Q1 of 2000. To aid in interoperability, many members of the WAP Forum have already signed Memorandums of Understanding, which state their desire to work together. The WAP forum is also developing authoring guidelines to ensure that developers can build applications that scale across multiple devices. With interoperability testing, certification and authoring guidelines, the WAP Forum will help to satisfy the interoperability demands of vendors, operators and developers.

About Phone.com
Phone.com, Inc. (Nasdaq:PHCM) is a leading provider of software and services that enable the delivery of Internet-based information services to mass-market wireless telephones. Using its software, wireless subscribers have access to Internet- and corporate intranet-based services, including Email, news, stocks, weather, travel and sports. In addition, subscribers have access via their wireless telephones to network operators intranet-based telephony services, which may include over-the-air activation, call management, billing history information, pricing plan subscription and voice message management. Phone.com is headquartered in Silicon Valley, California and has regional offices in Belfast, Copenhagen, London and Tokyo. Visit http://www.phone.com for more information.

Except for the historical information contained herein, the matters discussed in this news release are forward-looking statements involving risks and uncertainties that could cause actual results to differ materially from those in such forward-looking statements. Potential risks and uncertainties include, but are not limited to, Phone.coms limited operating history, potential fluctuations in Phone.coms operating results, uncertainties related to Phone.coms long sales cycle and reliance on a small number of customers, Phone.coms dependence on the acceptance of its products by network operators and wireless subscribers, Phone.coms ability to adequately address the rapidly-evolving market for delivery of Internet-based services through wireless telephones, the need to achieve widespread integration of Phone.coms browser in wireless telephones, competition from companies with substantially greater financial, technical, marketing and distribution resources and the ability of Phone.com to manage a complex set of engineering, marketing and distribution relationships. Further information regarding these and other risks are included in Phone.coms Form 10-Q for quarter ended September 30, 1999, in its prospectus dated November 16, 1999 and in its other filings with the Securities and Exchange Commission.

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