Fon Flash is a new program based on AP51 flash, for flashing La Fonera and Atheros chipset compatible devices. It has been tested, and works with the original 2100/2200 devices, as well as the newer Fon+ and Fon2.0 models.
The primary improvement in Fon Flash over AP51 flash is that it can flash several different types of firmware. While AP51 flash is suitable for flashing Gargoyle / OpenWrt, it cannot flash the latest official Fon NG firmware which requires three files to be flashed to the device, or the latest releases of DD-WRT (v24 and v24sp1) which require only one file. Fon Flash can flash all of these configurations.
Summary of improvements over AP51 Flash:
Using Fon Flash to install gargoyle firmware on your compatible router
Fon Flash is open source and therefore can be built and customized to your requirements.
Thanks go to the original author of Ap51 Flash, Sven Ola, and to Steven Leeman who has helped with testing and suggestions. Steven has also set up a site with instructions on how to flash original fonera firmware to any of the existing Fon models using Fon Flash.