The Get involved app seems to be indexing with much more support in deciphering handwriting. But I am not sure if I should stop indexing as I have done or go with the app.
The only things I see under Get Involved are indexing and "name review", and the latter still only has Spanish and Portuguese material, so no, I don't think it'll be replacing anything any time soon.
The Get Involved app supports computer-aided indexing (CAI). This approach has tremendous promise, and I wouldn't be surprised if CAI completely replaced traditional indexing at some point. But that time is surely several years in the future.
Traditional indexing is still very valuable. For one thing, it is available in far more languages than FamilySearch's current CAI offerings. It also takes considerable time to set up a CAI project and train the machine learning models. So there's great value in having both indexing approaches available for now, and I don't see that changing anytime soon.