New login screen

[overflorian]

The connexion screen is confusing and user tests show that it may sometimes be blocking for beginners.

To fix it, I propose to

1. redesign the connexion screen cf. proposal:
   Jungle Bus - design écran connexion V1.pdf

2. Enhance login possibilities
   Today it's possible to connect with a google account that does automatically create an OSM account.
   Make it possible to connect with a facebook account the same way too.

3. Postpone the moment when the login is needed
   Today the login screen pops up right after launching the app.
   Make it possible to test the app without login. The login screen may appear later, when:
   -the user clicks on the VALIDATE button while editing the details of an existing POI
   -the user clicks on the VALIDATE button while editing the details of a new created POI

These changes may appear in the Jungle Bus app as much as in the OSM contributor app.

[sdesprez]

Features such as forgotten password and creating a new account are not documented by OSM and does not seem feasible natively in the application. Available solutions are to either redirect the user to the website in his phone web browser or to display the website directly in the application.

I'm also encountering difficulties with Google and Facebook connection. They are not documented by OSM and they requires the user to already have an OSM account to link to the Google or Facebook accounts.

Considering those points, I've put on hold the redesign of the login screen until we reach a decision about those.

Since the point 3 is not impacted, I've externalized it to the new issue #163 in order to treat it in the meantime.

[juliencarnot]

I was surprised I couldn't log in the app with my osm account, having used it to log into other apps or sites (through Oauth): https://wiki.openstreetmap.org/wiki/Accounts#Many_other_apps...