Yes, it’s the 3rd new version of the android app, which is necessary to converge the ios and android apps together… to fix precisely the sort of stupid bugs which you were highlighting originally.

Element X is the new app, which implements the new faster sync and is built for performance from the outset.

Element R is an upgrade to the existing separate apps, which converges just the encryption on the new rust implementation, to minimise future encryption bugs by sharing the same code over all 3 platforms.

In terms of fixing perf, the solution is to switch to the new sync API (which will be supported on both synapse and dendrite) and use the new client codebase. Synapse and Dendrite are relatively similar in performance in comparison. Synapse dev will continue; Dendrite dev will continue focusing on embedded servers. Dendrite is very close to being stable, and yes there will be migration guides.

The status of Dendrite and its position vs Synapse is covered a bit in the Holiday Update: https://matrix.org/blog/2022/12/25/the-matrix-holiday-update...

The relevant section:

> The interesting plot twist is that Dendrite development has ended up increasingly focusing on embedded matrix server use cases - particularly to power Peer-to-Peer Matrix, where clients require a server to be embedded within them. So while Synapse has ended up increasingly focusing on large-scale deployments, Dendrite has ended up pursuing smaller instances (which is ironic, given originally it was meant to be the other way round!).

https://github.com/matrix-org/seshat - we’ve had it for years on desktop; just need to hook it up on mobile. it’s currently blocked behind unifying sdks, so we don’t have to do it twice in iOS & Android.