[Refefer]

Pragmatically, cost and ease of access is especially important in suppressed countries or ones with unstable infrastructure. While the devices you're talking about has lots of conveniences, distribution and price dominate in lower income regions.

For a side project, sure. But in first world countries, the odds of infrastructure breakdown or suppression of Internet is incredibly rare. In Iran's case, suppression is a weapon so phone only makes a lot of sense.

[VikingCoder]

I'd like to start with something that works, and then make it affordable.

Rather than start with something free, that demonstrably doesn't work where it needs to.