Claris Connect takes care of your automation with flows and connectors. If you miss a connector you are now able to make your own. One connector I am missing is to send simple push notifications, like if a flow is finished, if there are some errors etc. Pushover is a simple push notification service to instantly send alerts to Android and iOS devices. I have used Pushover myself for years. You need to buy an app (4-5 USD, a one-time payment) before sending push notifications free of charge to your device.
We made a custom connector for Pushover. You can read about it here, and it is published on Claris Marketplace. Maybe it is the first custom connector ever published?
Create a Pushover application
Once you purchased and downloaded the Pushover app for your iOS or Android device you need to create an account at Pushover.net, and connect your device. Please make note of your User key, you will need it when sending push notifications.
The next step is to create one or more applications in Pushover. Enter a name and a short description for the app. You can also upload an icon. The icon will be displayed on all push notifications. As you can see in the images below I uploaded a nice Claris icon.

For every application you will get an API token. Please make note of it.
Create a custom connector for Pushover
Since Pushover is not among the default connectors from Claris you will need to do a custom connector in Claris Connect. In your Claris Connect workspace there is, since today, a new menu option to make your own custom connector. Or, if you find a custom connector online, copy/paste the connector code to create your own connector.

A custom connector is created by writing JSON code defined by a schema specifying a custom connector.
To make it simple for you I have created the JSON code for a Pushover custom connector. Download it here: Download JSON for Pushover custom connector
The same JSON code is also available at Github.
When you click the download link you will see the JSON code for the custom connector in your web browser. Select all the JSON code (often Ctrl+A) and copy the code (often Ctrl+C).
Log in to your dashboard in Claris Connect and click the Custom connector tab, then click Create a new connector. In a large text field, "JSON input", you will find an example JSON code. Select all the code in the field (Ctrl+A), delete it and instead paste the code for the Pushover custom connector (Ctrl+V).

Click the button Save & Test at the bottom right. If it is disabled there are some problems with the code, try copy and paste it again.
To test the custom connector you have to authorise it. Click the button "Sign in" to the right.

Paste the API key and User key in respectively field, and then click "Test". You should immediately get a notification on your device.

Click Create Connector at bottom right to finish. The connector is created and you will now be able to use the Pushover custom connector in your flows.
Use the custom connector in a flow
In your Claris Connect flow you add an action. Select the Pushover connector in the Custom connector section.

Click Continue. Claris Connect will ask for authentication. Once again copy/paste your User key and API token from your Pushover account to respectively field in Claris Connect. This need to be done once per project, if you use the custom connector in another flow in the same project the same authentication is used.
After signing in with the Pushover keys you will once more get a test push notification to your device.
The last step before using it in a flow is to define the header and the message of the push. Select an appropriate sound for your push and save. As with any other flow step you can also select any data from previous steps in the flow.

The resulting push is displayed in the image below (delivered with a "magic" sound).
