Unless someone improved blockstream's implementation or mempool's implementation completely... you need a bitcoin core node, for either, the readme says:

So unless you hang something like a 1TB Samsung T7 disk to your android phone, this is not really feasible.

I think that you'd probably want LND with Neutrino if you're on an armv8 android phone, which is exactly what Blixt does on android, but then you get a much better management UI than termux, so you'd probably use that?