Why Weekly Active Users Is the Number I Watch in Tobi
Tobi went to public beta this week. Before it did, I picked one number to watch: weekly active users.
Tobi opened to public beta this week. Before it did, I set up three numbers to watch: downloads, signups, and weekly active users. I watch weekly active users most closely, because it is the only one of the three that tells me whether people actually use the app. A download just means someone tapped install, and a signup just means someone made an account. Neither one tells me whether a person used Tobi for the job it was built to do, but weekly active users does. Setting it up before launch meant that when people started showing up, I already knew what I was looking at.
How I define active
Tobi helps a household stay on top of home maintenance, so I define an active user as a person who added or completed a maintenance task in the last seven days. That action is what shows Tobi doing its job. Installing or opening the app does not, since a tap only tells me someone looked.
I count adding a task, not just completing one, because a person can be using Tobi well before anything comes due. Someone might spend their first week building out the maintenance schedule they care about without a single task falling due. If I waited on completions, that person would look inactive, even though they were doing exactly what I built Tobi for.
I settled on a seven-day window by ruling out the alternatives. A day is too short: household maintenance might not happen daily, so a daily count could sit at zero most days and spike whenever a task came due, telling me almost nothing. A month is too long: if usage starts to slip, I want to notice within days, not weeks. A week sits between the two, and as the beta produces real data I will adjust it to match how people actually use Tobi.
What I would miss without this number
Downloads and signups only ever go up. Watch them alone and the line keeps climbing while I feel good about the growth, even as people install Tobi, open it once, and never add a task. Those people came for help with home maintenance and left without it, and neither count shows that. Weekly active users is the one number that catches it. It separates the people who only tried Tobi from the people who got something out of it, and that difference is what tells me whether to keep adding features or stop and fix why people leave after the first open.
Defining an active user for your product
As an indie developer, downloads and signups are the numbers that will find you on their own. The app store shows them, your email list shows them, and both feel like progress. No dashboard hands you the number that says whether people actually use what you built, so if you do not define it, you will steer by the counts that only measure curiosity. Defining an active user is how you get an honest signal instead of a flattering one.
That definition is different for every product, so start by naming the single action that proves a person got the value you built the product to deliver: not the action you hope people take, but the one that means the product did its job. For Tobi, that action is adding or completing a maintenance task. For your product it will be something else, and you can define it before you ship. Do it early, and when people start showing up you already know who counts as active and whether the product is working.