I'm looking for a solid smartphone with a high-capacity battery. I don't care about performances: as long as Spotify Qobuz, Google Maps, Firefox and Lichess work seaminglessly, I don't care about running video games with demanding-graphics. I also would like to pay less than 300$, and I don't care about the camera. I also would like to keep this smartphone quite a long time.
Do you have other ideas (maybe a smartphone that is not rugged but has a strong battery)? Is the performance difference significant between the Doogee and the Ulefone? The only reason for me to get the Ulefone is the jack connection, as I would use it to plug my phone to my stereo (bluetooth connection is shit to stream music, and I don't yet have more sophisticated streaming devices).
Why not get a $250 Xiaomi with Snapdragon SoC and a $50 powerbank? You'll get a much better experience performance and updates-wise and battery might even be better due to the better SoC.
I really wouldn't recommend Doogee or Ulefone. Anything you gain from the battery capacity (which might even be a lie!) is cancelled out by horrible kernel+OS tuning and Mediatek SoC.