hi Nik47 how you managed to upgrade Lumia 735? I bought a new lumia 735 and can't find a way to upgrade it. I thought 730/735 were similar but now I am very disappointed that my Lumia 735 purchase is useless right now
Ok, it seems I am not allowed to post links yet, so typing out this reply for the second time.
I can understand your frustration - it was the same for me as there aren't any articles mentioning 735 being upgraded. Here's what I did - may not be the best way of doing it but it worked for me. Note that you will have to reset your phone at some point in time and that means pulling in apps and data again into the phone.
I assume you have signed up to Windows Insider and have downloaded the app on the phone. In the about section of the app, ensure that sys free space is at least 600,000,000 (it was for me - I install my apps and music on my SD card). If not, reset the phone and install only the windows insider app.
Since I can't post links, on the XDA developer forums, search for an article called "Get WP 10 for every Windows Phone and everyone with 3 easy steps". Follow the steps in there carefully.
Now here's the key step: Ensure that you reset your phone after WP10 is installed. Choose language and region as US to retain Cortana.
I can assure you that the OS is a bit buggy and some features like tetra lock screen app and the phone's sensor core is not supported. But like me if you cant resist trying out something just because you can and are prepared to stay up late with software recovery tool handy if the phone get's bricked, then I hope these steps work for you too
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