Back in early May 2019 I blogged about the Lumiya Viewer being no longer listed on the Google Play Store. Apparently it was removed from Google Play due to a change in the developer terms (change in SMS policy from Google). Lumiya was removed off the Third Party Viewer Directory page for a variety of reasons.
The Lumiya website was last updated in early October 2017 and the latest viewer version was 3.4.2. There has been no word from Alina Lyvette for some time now and it seems unlikely that the Lumiya app will be updated again anytime soon. Myself and many others have tried to get in touch with Alina but so far there have been no responses.
The Lumiya Viewer is still available through Slide.Me (risk) and other websites which may be risky. The last version still offers communications and other viewer functions. However from what I have heard the world rendering and avatar appearance etc are broken.
I hope someday we will hear from Alina Lyvette. For now it’s worth waiting for announcements on the iOS and Android version of the new Second Life mobile app that Linden Lab are working on now.