Getting connectException: failed to connect to localhost/


I have formatted my android phone - this was working before perfectly.
I have my code in my mac book - and I do "yarn run build && concurrently “yarn run watch” “yarn run start”
on the expo app version 2.6.4 on Android phone version 6.0.1

I get error on expo app: failed to connect to localhost/ after I scan QR code.
I saw solutions online, but are mainly with windows or disabling firewall - I am unable to find same options in my kind of setup. Please help


Hi @chaudharynitesh!

When you run the yarn run start, what is the URL that Expo prints out to use (right under the QR code)?

For me, for example it’s:

[09:50:41] Your URL is: exp://

If your URL is something like, try running yarn run start with --lan option and then scan the QR code (run exp start --help to see other options):

    -m, --host [mode]     tunnel (default), lan, localhost. Type of host to use. "tunnel" allows you to view your link on other networks
    --tunnel              Same as --host tunnel
    --lan                 Same as --host lan
    --localhost           Same as --host localhost

Running the packager with --lan option makes the packager use not (, but some other URL that is more likely to be accessible by your phone, if they’re connected to the same network.

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