You open a remote app, it finds your Roku, and then nothing happens when you press a button. Most of the time this isn't the app or your Wi-Fi: it's one setting on the Roku.

Why does my Roku ignore my phone?

Newer Roku software has a setting called Control by mobile apps, with three levels:

Enabled: phone apps can control the Roku. This is what you want.
Limited: the Roku answers the app, so it shows up in the list, but it ignores most button presses. Many Rokus are set to this.
Disabled: the Roku refuses phone apps entirely.

How do I fix it?

Use the Roku's own remote one last time (or the TV's remote on a Roku TV):

On the Roku home screen, open Settings.
Go to System, then Advanced system settings.
Select Control by mobile apps.
Set it to Enabled.

Remofy, a free Android remote, checks this setting before you even tap the Roku: the list says "Needs one setting on the TV", shows you the steps, and connects by itself as soon as you switch it to Enabled.

The setting is Enabled, and it still doesn't work. What else?

The phone is on another network. It must be the same Wi-Fi as the Roku, not a guest network, and with any VPN off.
The router keeps devices apart. Some routers have "AP isolation" or "client isolation" turned on, often on mesh or guest networks. Turn it off for your main network.
The Roku is asleep. Press a button on the Roku's remote or the TV. To wake a Roku TV from the app, turn on Settings > System > Power > Fast TV start.
The app is out of date. Update it from the Play Store, then close and reopen it.
Everything else looks right. Restart the Roku (Settings > System > System restart; on a Roku TV it's under System > Power) and your router.

I lost the remote and the setting is on Limited. Can I still fix it?

You need a remote once to change the setting. A replacement Roku remote is cheap, and a universal infrared remote set up for your Roku TV works too. After that, your phone does the rest.

Frequently asked questions

Is there a free Roku remote app without an account?

Yes. Remofy needs no account and no subscription. It also controls Samsung, LG, Fire TV, Vizio and Google TV, so one app covers every TV in the house.

Why does my Roku show up in the app if it won't respond?

In Limited mode the Roku still answers "who's there?" on the network, so apps can list it. It just refuses most commands.

Will the Roku remember the setting?

Yes. Once it's on Enabled, it stays that way until someone changes it.

Roku Remote App Not Working? Check This Setting