RALEIGH - Congress wants to know how much data usage the Pokemon Go app is taking up.

Lawmakers sent a letter to Niantic, the company behind the app, asking for more information and if customers have been warned.

The wildly popular smartphone app allows players to locate virtual creatures using their GPS. However experts say if players aren't careful, they could run up their cell phone bill because the app uses a lot of data.

"With these games, such as Pokémon that are really extremely popular, the data usage is significant," says Sprint District Manager Joseph Hazeldine.

UNC-Chapel Hill student Daniel Salgado says he plays Pokémon Go, and was surprised that he used up more than two weeks worth of cell phone data.

"I took about a three or four hour trip around town to try and collect some Pokémon and noticed that I burned through approximately 6GB of an 18 GB plan," he says.

Various studies disagree on how much data the app uses.

Verizon released this statement:

“Our customers using Pokémon GO have not seen dramatic data consumption waves. The app sends information in bursts rather than streaming – as a video service does – so GPS location is the most data-intensive task it completes. The app represents less than 1% of our overall network data traffic on the Verizon network.”

However, experts offer some tips such as using a Wi-Fi network wherever it's available. If one is not, they recommend making sure the Pokémon Go app is the only one running.

"If you play for more than a couple of hours at a time, that’s where you run into risks of actually using a lot more data," says Carlos Saura of the Best Buy store in Cary.

Saura also adds that avid users buy a bigger cell phone data plan.

Salgado says bottom line, to just monitor your data and your battery usage.