Muun tries to simplify by having one address to send and receive to lightning or basechain wallets. When fees are high muun gets exposed but not really using lightning. It's a workaround for ease of use.
Phoenix and Breez are running lightning nodes on your phone. They are cool but there is a learning curve. We are still in the very early days of this and seeing the speed of lightning payments is super exciting.
I completely misunderstood that app until today. I tried to move 10,000 sats to try a Phoenix wallet and the fee was so big (131,000 sats) that it wouldn’t do it bc i lacked funds! Possibly similarly bad I deposited $25 usd into strike to get some quick sats to play with Phoenix and Strike only gave me 9000 instead of 90000 sats. I still haven’t heard back from them regarding why that happened.
Yikes, that’s a lot of sats! If you don’t mind waiting (potentially a long time) usually you can set a lower fee manually. 
BTW. I think I have to correct my misinterpretation of the sats strike sent me. They send me 0.0009032 and I interpreted it as they shorted me. I thought this bc the last decimal was missing and bc I had visually compared it to my last 25 dollar order of 0.00090914. Not that you care but I didn’t want to let it slip that I made a mistake.
