Beware the way you code it must stay within the abilities of the devices you wish to code for. Not everything Flash does is supported on every platform. Devices are most limited.
Pre-plan your assets (images/video/audio/etc) in a format suitable for all your targets and keep the quality and resolution as high as possible to start so your desktop version will look and work great. Then be prepared to reduce the quality and have code capable of handling either a new layout/form factor as the screen resolution goes down for devices.
Be prepared to work with some variable hardware. Androids especially have all sorts of different resolution screens and varying hardware support. Just plan plan plan.. Most of your codebase will be re-usable if you continue to think and code like this.
