First things first, open up your Adalo project where you want to add that snazzy countdown timer component.

Head over to the left sidebar and hit the “+” button. This will open up the component marketplace for you.

In the Component Marketplace, just type "Countdown Timer" into the search bar at the top. When you find it, click on it to add it to your project.

Now, drag and drop the Countdown Timer component onto the screen where you want it to appear in your app.

Click on the Countdown Timer component to open its properties panel. Here, you can set the countdown time by entering the number of hours, minutes, and seconds.

Scroll down in the properties panel to the “Actions” section. This is where you decide what happens when the timer hits zero. You can choose actions like navigating to another screen or triggering an alert.

Customize the look of your countdown timer in the properties panel. Adjust colors, fonts, and sizes to make it fit perfectly with your app's theme.

Click on the “Preview” button at the top right corner of the Adalo editor. This lets you see your countdown timer in action and make sure everything's working as it should.

Once you're happy with how the countdown timer looks and works, save your changes and publish your app by clicking the “Publish” button in the Adalo editor.