Here, I took a look at all the solutions major smartphone manufacturers are using in their interfaces to improve one-handed usability of their smartphones.
Approach 1 : One-hand mode
Used by : Xiaomi, Vivo, Realme, Oppo, OnePlus, Samsung, Motorola
1. Every touch target in the UI are closer to the thumb.
1. Text size gets reduced affecting the readability of content.
2. The size of touch targets in the UI gets smaller than required in Google's material design and Apple's human design guidelines.
3. Use of screen area is very poor as almost half of the screen is blocked.