maresca

I'd like to replace the native call/text functionality in Android. I'd like to build an Android app that will handle incoming/outgoing calls/texts using Twilio. A wifi-only phone of sorts. I've built Android apps in the past so I'm familiar with the process. My knowledge of modifying code on a rooted android device is lacking. What I need help finding is how to override/hack the lock screen to show incoming calls. Incoming text messages can be handled with normal push notifications. Lock screen widgets were removed in Lollipop so I can't go that route. I'm looking for any pointers, helpful info, code examples, or comparable apps. I'd like to make sure this is feasible before committing any amount of significant time to it.

I'm currently testing out Canvas JS libraries. I'd like to build a simple paint type of web app using Canvas and JS. I'd like to be able to create layers, draw, erase, etc. I tested out PaperJS, but it seems PaperJS is more geared towards SVG and fails at erasing. What popular Canvas JS libraries is everyone using nowadays?

What do you use to transfer links and files between devices/computers/tablets/phones/etc? Email? FTP? NAS? I'm looking for a good, seamless solution for this.