I have been using the s24+(snapdragon gen 3 version) for about 2 weeks and would recommend it. I have obsidian set as a “Never sleeping application” and pretty much every time I have to the application it is still open. I also tried force closing and the loading is much faster than on the pixel 8. Somewhere between 2x and 5x faster. Installed dataview and that is faster as well.
You can also use the samsung “keep open” feature. It drains the battery more, but also seems to allow obsidian to sync even when not actively open. With “keep open” enabled, obsidian has more battery drain than any other app. Usually in the realm of 3%-6% of the total. Without just “never sleeping application” enabled. Obsidian is 2nd or third in usage and more like 2% of the total drain. I get a full day of battery even when I use “keep open”.
The s24+ has 12gb of ram. I would guess that the “keep open” feature would still keep the app open for samsung phones with 8gb and maybe lower.
TL;DR I would highly recommend samsung phones over the google pixel line. Obsidian stays open and is faster to load.