For yourself
1. Samsung S25FE, or Samsung S24FE, or iQOO 15, or Oneplus 15 (all supposed to have atleast 6yrs OS upgrades)
Chance of green lines on display cos of Samsung screen tech
Can also consider Xiaomi flagship series
2. For banking apps / security / tracking protection - iPhone 16, or iPhone 16e (supposed to get 6yrs of OS upgrades, probably even longer)