We use this tool every day at Radio.co
Notice Revenue often doesn't work on 1st of the month though..?
Although simplicity is good it would be cool to see more functionality.

Monitor key SaaS metrics like Monthly Recurring Revenue, Annual Recurring Revenue, and total customers. This app connects to your ChartMogul account via API to display essential business numbers.
0.9
October 21, 2016
This app has been updated by Apple to display the Apple Watch app icon. Fixed "white screen" bug. App should work fine again. So sorry about the white screen some of you have experienced.
MoreRevenue Tracking displays your Monthly Recurring Revenue (MRR), Annual Recurring Revenue (ARR), and your total number of customers. These are the core metrics for understanding your SaaS business's financial health.
Revenue Tracking uses the public API of ChartMogul to access your business numbers. You will need to provide your ChartMogul Auth Token from your ChartMogul settings to connect the app.
ChartMogul, and by extension Revenue Tracking, supports data from payment processors like Braintree, Stripe, Recurly, and Chargify. This allows for a comprehensive view of your recurring revenue.
No, Revenue Tracking is not officially developed by ChartMogul. It is a third-party application that utilizes ChartMogul's public API to display your business data.
Revenue Tracking is available for iPhone and iPod devices. It is designed for Apple's mobile ecosystem.
The latest version of Revenue Tracking is 0.9, last updated on October 21, 2016. The app was initially released on July 31, 2015.
Revenue Tracking has an age rating of 4+, making it suitable for a wide range of users. It is a simple utility app with no mature content.
No, Revenue Tracking does not contain advertisements. The app is free to download and use without any ad interruptions.