Since I try to save in btc as much as possible, I end up spending btc more often (still to my net benefit)

I use Binance, Belo, Lemon, and for a pure wallet, Muun. It's actually a breeze to use crypto here, we are startled at how restricted crypto is in the USA, where we would expect it to be even more easy to use than here

Which wallet do you use? 

Binance? 

Spend tether 
Hold bitcoin 

Bell_curve

If you mean apps, all in existence for now: Binance, Lemon and Belo.

Can you estimate how many retailers have integrated Lightning?

GhostofTruth

Yes, USDT is the de-facto standard. But I prefer to keep everything BTC, I don't keep money on USDT for too long, DCA is very efficient