# Enabling Phone Authentication

To enable phone/otp authentication on your app , just follow the video guide below.

{% embed url="https://www.youtube.com/watch?v=HWOaD4JDSOM" %}

{% hint style="info" %}
Make sure to add your number for testing else firebase will block your number if you try to send otp to the same number. Also to send OTP to other numbers, you will first need to sign your apk with key you generated above.
{% endhint %}

To generate App Signing key , run&#x20;

```
keytool -genkey -v -keystore yourkeyname.keystore -alias youraliasname -keyalg RSA -keysize 2048 -validity 10000
```

To get SHA1 key, run

```
keytool -list -v -keystore yourkeyname.keystore -alias youraliasname
```

{% hint style="info" %}
Make sure to copy your **google-services.json** file inside **sourcecode** folder
{% endhint %}
