Motorola Mobility changed the launch target date for Bionic, its next key phone for Verizon Wireless to this summer, potentially making the device a quarter later than expected.

After promising in January that the high-speed wireless phone would hit shelves in the second quarter, Motorola said on Tuesday that it now expects to sell the Bionic this summer, which officially starts June 21, days before the end of the second quarter.

Motorola said it was changing the launch target date so that it could add new features to the device and change its form based on feedback it received since it showed off an early copy of the phone at a gadget show in January.

Verizon Wireless, a venture of Verizon Communications Inc and Vodafone Group Plc, has been Motorola's most important customer for the last year as it helped the company regain some market share lost to rivals.

But soon after Motorola Mobility became an independent company this year, Verizon, the biggest U.S. mobile provider, took on another key phone supplier, iPhone maker Apple Inc making it tougher for Motorola to compete.

(Reporting by Sinead Carew; editing by Carol Bishopric)

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