When I go to run the application, my device no longer shows up in the chooser dialog. Developer options and USB debugging is still enabled no my phone, and I made sure the target SDK of my application is 23. Anyone else have this problem?
I had the same issue. The following steps seemed to fix things for me.
In Developer Options, in the USB settings, choose "Revoke Authorizations" to clear all authorized devices.
In the main Android menu, when connected via USB you'll see an alert that says "Connected as a charging device" or some such thing -- click on that, and choose "Transferring media files". After that, it should say, "Connected as a media device" and it will show up in ADB as an unauthorized device (because we revoked authorizations earlier).
Now connect and disconnect your device (maybe unplug the cable and plug it back in?) and the phone should prompt you to authorize your PC. If it doesn't, try doing the second step above (setting as a media device) until the popup asks you to authorize your PC. Authorize it, and now you should be able to use ADB like normal.
Hope that helps?