Neoway M590 GPRS tutorial on sending and receiving files from/to SD card from Vadim Panov:
Here’s a bit of useful info from what I’ve been doing lately. I got a job to design a device that connects to a web-server via GPRS and downloads a bunch of tiny WAV files, that it later plays on a specific schedule. Now, there’s a jellybean part for this kind of task, and that is SIM900 (or SIM800), but I have a knock for “optimising” my electronics. Optimising in this context means making everything I can as cheap as possible, provided it doesn’t impact overall quality in a negative way.
That’s how I came upon this el cheapo GPRS module – Neoway M590. It’s sold as an assemble-it-yourself kit at Aliexpress, and at the moment of writing this article it retails for as low as 2USD.
More details on Vadim Panov’s blog.