The “without ads” part is hard to get right, I think. Many podcast publishers start to include ads, so AntennaPod is not ad-free for users. It’s just that the app does not add more ads. This is already confusing to some users who leave bad ratings on Google Play 
I have made the experience that many average users do not know what open-source even means. Highlighting it in the screenshots could be confusing. On GitHub, we discussed about renaming the developer name to “AntennaPod Open Source Team” to have it mentioned somewhere. This will need some time, though, because the Google Play account is the private one of the old maintainer. I think that we might be more flexible when registering a dedicated Google Play account for AntennaPod.