[jekub]

But I'm in their target market and I don't want a replaceable battery. I just want the battery to be serviceable when it wear.

For a given phone size, a replaceable battery require some additional space which means it will be smaller than a non-replaceable one.

I don't want to buy one or two additional battery to carry with me when I can get a battery that last a bit longer and that I can charge with any power bank. (mine or the one of a friend as there is no compatibility problems)

Users who want replaceable battery are niche in the niche.

[Wowfunhappy]

I highly doubt this phone is going to win the thinness wars anyway, so the space savings aren't going to be as relevant. It would be much smarter to differentiate themselves on features such as replaceable batteries, which the mainstream market has ignored precisely because they want to chase thinness.

The real question is, how many users want replaceable batteries, and is there enough overlap between that group and the audience for an OSS phone. I would imagine the overlap is significant, but without market research on the subject I don't know if I'm right.