Few things to touch on here.
You cannot tell how significantly faster the processors are because 1. Your phone is already very fast enough. 2. Unless you’re doing a specific real time image processing.
iPhone camera will always be the superior one over Android. You’re talking about inferior post-process photos. Android uses a lot of AI under Google’s API to articulacy boost your photos. They are not organic.
For battery life, since you are in Singapore, the battery life will always be worse than those in the US. This has to do with the mobile data power efficiency. For some reason US telco has a more power efficient 4G than Singapore’s 4G. Technically US uses LTE which is slightly different from Singapore’a 4G. The in-depth details are very technical.