Yep, that's one of the side effects - you can plug some 2.4G transceivers (like NRF24L01, using an adapter) in the expansion port to talk to 2.4GHz stuff, or use some TI sub-GHz chips for 433/900/868. Also, I'm wondering about POGSAC (the networking standard that pagers use) - somebody on Hackaday suggested it to me, and soon, when I'll have some free time, I'll get some POGSAC receivers and will make a test environment (as in, imitate a POGSAC basestation for testing).
Awesome! I'm really curious to hear how that goes. Is it best to follow https://crimier.wordpress.com/ for such things and/or do you tend to post about your projects elsewhere?
I generally post all things ZeroPhone on Hackaday.io - https://hackaday.io/project/19035 - the blog is just for short random notes that might be useful to someone.