Custom Bootloader to Upload Sketch with 1way communication

I’m wondering if this is possible.

The goal: To upload sketches to embedded ATMegas32U4s (Arduino Leonardo) from iOS/Android apps via a serial Bluetooth connection.

Resetting the ATMega to trigger the bootloader is no problem, using one of the bluetooth modules GPIO. Then I’d like to send my compiled sketch to the device. To keep things reasonably simple and to use the same technique between iOS and android apps, this should be a one-way data transfer and not require anything more than sending a file by serial. I think it’s likely possible to adapt avrdude to my apps in some way, but I feel this would be overly complicated.

So, is this even possible? Could a custom bootloader be made to receive a sketch in this manner? Any other ideas that would accomplish the same goal are appreciated! Thanks!

ps. If it is possible, I’d be looking to hire someone to do this.

bluetooth wireless serial port protocol. Use existing serial bootloader. Wire UART on microprocessor to bluetooth device with serial port. Mind the voltages: 3.3 vs. 5V. web search for Bluetooth serial profile supporting devices.

OR

Get a WiFi to serial adapter for the microprocessor end. Then use an app that matches.