One of the best-selling video game consoles of all time is the Nintendo Entertainment System, better known by its acronym, NES. However, cartridge-based gaming consoles are a pain now when compared to the newer download-and-play alternatives.

If you miss the days of old school side-scrollers like Super Mario Bros., or the puzzling nature of The Legend of Zelda, but don’t want to dust off your bulky NES—turn your HTC One into a mini-NES that fits in your pocket.

All it really takes is the right emulator and a few game ROMs.

Step 1: Install an NES Emulator

The first thing you’ll need to do is install an NES emulator on your HTC One. There are tons of emulators in the Google Play Store, but I’ll be using John NES Lite by John Emulators.

Step 2: Copy Game ROMs to Your Device

Now you’ll need to copy some playable game ROMs to your device. If you’re technical enough, you can convert your old NES games into ROMs, but they can be easily acquired online using a quick Google search.

They may be illegal to use in your country if you don’t already own the game, so a rule of thumb is, if you don’t own it, don’t download it.

John NES Lite supports ROM-based games in .nes and .unf formats, and additionally in .zip files. Once you have a couple NES game ROMs, if you didn’t download them directly onto your HTC One, you’ll need to transfer them over from your computer.

1. Create a folder on the root of your internal storage. I named mine ROMs.

2. Create a folder inside of the ROM folder called NES and copy the ROMs into that folder.

3. Disconnect the device and open the John NES Lite app.

Step 3: Load Your Games

As soon as you open the emulator app, it will find the games and list them on the main screen. Tap the game you want to play and get started!

Playing the Games

Overall, I found the experience of playing games on the HTC One pretty easy. The BoomSound speakers make the game audio crystal clear and the phone ran the games well in portrait and landscape orientations.

Occasionally, it was difficult to press multiple controls at once, but there are some third-party game controllers you can use with Android, like the POWER A MOGA Gaming System, which works really well.

John NES Lite will save the state of the game that you’re playing when you exit the app, but if you want to save and load states, you’ll have to purchase the full version. More on that later.

Downloading Games from Within the App

If you had a hard time figuring out how to get ROMs earlier, the app has a feature to find ROMs built inside. Just tap the menu button and select Find Games.

John NES (Full Emulator)

If you don’t like the idea of playing without being able to load save states, you’ll want to upgrade to the full version of John NES ($3.49), which also gives you turbo buttons, X2 speed play (i.e. double speed), and some Game Genie and PAR cheat codes.

However, if you’re just looking for a quick way to reminisce, John NES Lite will do the trick.