Add a force upgrade path?

[Gregliest]

Basically, how do we want to encourage or force people to upgrade the app? Android users are generally bad about upgrading, and if we ever deprecate part of the API, or make other breaking changes, we may want a way to make sure no one is using the affected old versions.

There are generally two ways to go about this:

1. Soft upgrade (dismissable)

• Something like an in app modal or push notification that's dismissable, alerting the user that there's a new version, and/or that their current version is now broken.
• Pros: Not as intrusive.
• Cons: Not 100% effective.

2. Force upgrade

• Lock the user out of the app with a link to the Play store to upgrade.
• Pros: It guarantees that we get users off the affected old versions.
• Cons: It's obviously intrusive to the user.

In my opinion, if we include a force upgrade code path, it should be for emergencies only. Emergencies can include hotfixes (if we release a version that is unusable for some reason). I would generally shy away from using the force upgrade to move users off of old versions, unless those versions are REALLY old, and they are becoming a significant maintenance burden.