 Pocket PC 2000 , originally codenamed " Rapier " , was released on April 19 , 2000 , and was based on Windows CE 3 @.@ 0 . It was the debut of what was later dubbed the Windows Mobile operating system , and meant to be a successor to the operating system aboard Palm @-@ size PCs . It retained backwards compatibility with such Palm @-@ Size PC applications . Pocket PC 2000 was intended mainly for Pocket PC devices ; however , several Palm @-@ Size PC devices had the ability to be updated also . While , several Pocket PC 2000 phones were released , Microsoft 's smartphone hardware platform was not yet created . The only resolution supported by this release was 240 x 320 ( QVGA ) . Removable storage card formats that were supported were CompactFlash and MultiMediaCard . At this time Pocket PC devices had not been standardized with a specific CPU architecture . As a result , Pocket PC 2000 was released on multiple CPU architectures ; SH @-@ 3 , MIPS , and ARM . Infrared ( IR ) File beaming capability was among the original hardware features . 
