a little more research-

- the phone I'm using has a 1900mAh battery, and claims a standby battery life of 281 hours, which means it draws about 7 mAh per hour at idle. I imagine with the app which probably keeps the camera on all the time for motion sensing, it's probably double or quadruple (30 mAh is a safe estimate).
- HF sells a solar trickle charger rated at 1.5 Watts at 24 Volts, which works out to 62.5 mAh, for $13.99, solar won't work at night, but hey, neither will the camera unless I get some motion activated lights. I'll figure out the middle of the night stuff later.
- I'll make/buy a waterproof enclosure from Walmart for less than $10, and run some extra wiring from the USB charge port on the phone to the solar panel
- I'll pay $9/mo for 500 mb Data plan from USMobile, (may have to buy more bytes if needed, but this is the cheapest plan I've found)
-- later I may just get a wireless router with a sim card slot and distribute my USMobile data plan among many smartphone cameras- have them all connect via wifi to the router, then the router will send photos/videos/sound via 3G/4G.

I'm going to set this up facing the cars in my driveway (we've had break-ins in the past in our cars when they weren't locked. Even when they are locked, I imagine the thieves check them every night for us to make sure they are locked). I'll see how it works, then go from there. so that's where I'm going with this.