1. Never use multi-crap coins wallet apps. Bitcoin only.
2. On a LN wallet do not put too many funds, just enough to be able to pay your daily expenses.
3. Use 2-3 apps (or more), not just one. Not only because you can have multiple choices, but also be prepared in case one could fail a payment.
4. Use only well known and tested wallets. Beta version - use with caution!
5. Spend through LN in high fee moments, and swap in more sats when the fees go lower. In this way you are always prepared.

Literally scams in LN, I am not aware of them. Mostly are user mistakes or bugs.
As a general rule: always use the 3 levels stash - hodl, cache, spending.

Over time, some greedy entity we creep into LN but we ain't there