I have a trick you should try if it seems like your phone is constantly dropping a data connection. Turn off your Wi-Fi. I know, it sounds silly, but let me explain.

Here’s the scenario: you’re walking down the street trying to find directions in Google Maps or streaming music, when suddenly Google Maps won’t load and Spotify stops streaming. It happens to all of us.

There’s a chance you’ve simply wandered out of a data coverage area, but it’s becoming rare now that wireless networks pretty much blanket the United States in high-speed data. Instead, it’s more likely that your phone has latched on to some open wireless network that’s not providing any service, even if your phone thinks it is.

There’s a reason this happens: sometimes your wireless network, like AT&T, might have free Wi-Fi hotspots all over a city. It can be convenient if you’re using a laptop, but sometimes your smartphone will automatically connect to those networks even if your regular cellular connection has a faster connection.

Apple released a fix for this in iOS 11, which was supposed to prevent iPhones from connecting to poor Wi-Fi networks, but I’ve found that this can still sometimes happen on Android and iPhones alike. Sometimes it’s good, if the Wi-Fi signal is solid, but usually it just gives me a slow or terrible connection. Here’s how to fix it.

Source: Tech CNBC
Try this trick if you think your phone keeps losing a data connection