Where are the flip phone app stores?

My daughter's slide-out keyboard phone died and, instead of getting another one right before Santa might bring one, we got a cheap flip phone for her so she could reach us in the meantime. We got a Samsung T139. Only $20.

The first thing that struck me about it (reminded me, more like, since we used to all have flip phones) was that it was so tiny and light. It's only 2.96 oz versus 4.9 for a typical smart phone. Also, it fits into a pocket trivially, and doesn't stick out (and slide out, sometimes) like a smart phone "tablet". The battery lasts 12 days. That's "days", not "hours".

I wonder why we left such phones, and so quickly. To surf the web and read email? Perhaps but those are not easy to do on a phone, especially writing. I'm certain there was a "coolness" factor involved. We can probably lay some blame on "Angry Birds".

[ In all honesty, map apps are a crucial use for smart phones. The built-in GPS, big screen, strong CPU and data connection make a fairly killer combination. ]

One thing that smart phones let us do is write our own apps. Smart phones are general purpose computers so one can put all kinds of little apps onto them, some that even make sense to put onto a phone. A pedometer, for instance, makes perfect sense to put into a small device that you always carry with you. It doesn't require an extensive user interface. It doesn't even need to upload the data anywhere, but it could.

I've heard that flip phones are making a come back as people migrate their heavy viewing to tablets. I wonder if this would only accelerate if flip phones had "app stores". For instance, one tiny app that I like to have is the OTP generator for my email account. I ported it to my Pebble watch; why can't I put anything on a flip phone? *Does* anyone make an open flip phone? Could we convince Samsung to open theirs?

It vaguely appears that these phones can run Java applets. I don't know if the applets have to come from webpages, or if they can also be loaded locally. There may be hope there; Android uses Java almost exclusively.

A killer feature for flip phones would be the ability to run SIP (either over wifi or cellular data). SIP users tend to be fairly frugal. What's better than a cheap phone on a cheap phone network?