It is necessary to have a pc to use PocketFMS.
PocketFMS installs onto your pc, and you update your pda from there.
All updated navdata is downloaded by the pc, and then transferred to your pda.
The pda can do all functions required inflight.
Can't see why someone would buy Flightmap, when all it does and more is available for free with PocketFMS.
Can you tell I'm a fan?
dp