Sure, why not? I wrote several guides and here you have some that you could run two powerful private nodes on your mobile device: - https://darthcoin.substack.com/p/getting-started-zeus-mobile - https://darthcoin.substack.com/p/getting-started-with-blixt-mobile
Why not is the question. Is there a disadvantage in having just private channels? Is it more likely a route to fail for incoming payments with only unannounced channes? For small payments never. For bigger one (like 0.005) I can't tell if it's because of bad connection or discoverability (if it's a word)