iOS Beta installation process
Install TestFlight on the iOS device that you’ll use for testing. Open your invitation email or tap on the public link on your iOS device. Tap View in TestFlight or Start Testing; or tap Install or Update for the app you want to test.

Info
If you already have the App Store version of the app installed on your device, the beta version of the app will replace that version. When you’ve downloaded the beta app, you’ll see an orange dot next to its name that identifies it as a beta.

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Android Beta installation process

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Windows Beta installation process
Click on the Beta app Link that you have received in Pulsar Notification Email. Click on Download button. Once appxbundle file is downloaded on your device, Click on the file. Click Install button to Install Pulsar Beta app on your device.

Warning
If Pulsar is showing certificate error while installing the app, user will need to install certificate on device using below steps.

Steps to install Certificate

Save the .appxbundle on the computer you want to install this on
Right-click on the .appxbundle package and select properties.
Under the Digital Signatures tab you should see the test certificate. Click to select the certificate and click on Details button.
Select the button View Certificate.
Select the button Install Certificate.
From the Store Location radio buttons select Local Machine. Click the Next button.
Click Yes on the admin prompt for changes to your device.
On the Certificate Import Wizard chose the radio button Place all certificates in the following store then select the Browse button.
Select the Trusted People certificate store. Then click the OK button.
Click the Next button on the Certificate Import Wizard window.
Click Finish button to complete the certificate install.
You can now close all windows and double click on the .appxbundle file. It should now install properly.