Upgraded my phone from win 8 to 10moble. Internet slowed to crawl.just like the good old days of dial-up.i tried to reinstall no improvement. Tried using opera mini very slight speed increase.doesn't matter if I'm connected to cellular data or using WiFi.
Can you check to see what OS version you're on? You can check in settings > system > about > OS build
Second, can you check for app updates? In store
What did you try to reinstall?
For wifi, did you try to remove the network from your phone and then add it back?
For cellular, have you checked that you're getting good coverage and 3/4G?
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