I'm posting this here because it is a general question and covers more than one platform, so the specific platform forums do not seem logical homes for it - mods feel free to move if you think it deserves a different home!
I use Newton email to manage my email on Mac OSX, Windows, iOS and Android. It looks and works the same on all of those, which is important to me - I do not want to be trying to run different Mail apps on every device. At present I have no Windows needs but in case I do (I did) I need one that works there too.
Newton is being shut down, which is a shame but which was probably inevitable once they started charging real money for it. I did not mind paying - the app was very good and people have to eat; I would rather pay a straight transaction fee than have my data sold or be advertised at all day to be honest.
Looking for GZ recommendations for a good replacement (not Outlook - don't get on with it). It needs to work on all those platforms and be able to combine Apple email addresses and Gmail email addresses. There are heaps of very nice ones for the Mac side of it but often they do not have Android versions.