Apple Watch Screenshot 2We knew we wanted to have the Betterment mobile app on the new Apple Watch when it debuted this spring. A Betterment watch app would not only provide our customers with another way to invest when and where they want, but it would also be an engaging way to show off our design and user experience.

To build the app, we faced a complex problem: Watch apps encourage quick and effortless reactions to timely information, like responding to a text message or replying to an invitation, yet Betterment encourages a thoughtful and deliberate approach to long-term investing.

Betterment encourages a thoughtful and deliberate approach to long-term investing.

So, then, how to create a watch app that met Apple’s watch requirements, stayed true to our buy-and-hold investing philosophy, and delighted our customers?

Before we even had a watch in hand, we explored some “blue-sky” ideas that would allow customers to:

  • Keep tabs on timely, up-to-the minute information
  • Receive behavioral feedback about mood during actions via heart rate/motion sensor
  • Enable impulse saving

Two of these ideas just didn’t work quite right; the first because it wasn’t part of our investing philosophy, and the second because it was hard to execute because of interactions with TouchID, the keychain, or other bugs in the API. Ultimately, we were able to execute on the third idea.

As transparency is one of our core product principles, we thought we’d open up our thought processes about how we considered each option.

Option 1: Focus on timely information.

Initially, we tried to build a watch app that surfaced new, interesting data every time customers glanced at their wrists. This caused us to focus on information that changed rapidly, like minute-to-minute market fluctuations, portfolio drift, and whether the market was open or closed. This data is common in other financial apps, but it facilitates reactionary decisions rather than the kind of passive investing we encourage.

The verdict: A constantly updating app would encourage bad investing behavior.

Option 2: Focus on novel watch features.

Once we decided against presenting ephemeral data to the customer, we looked for other ways the Apple Watch could enhance the Betterment experience. We toyed with using the watch to measure a customer’s heart rate during allocation changes, therefore identifying physiological patterns associated with withdrawals or deposits. We also considered letting customers sketch something fun on the screen to initiate a deposit. But, while these applications could have delighted our customers, the Apple Watch’s restrictive environment, unfortunately, prevented us from running with them.

The verdict: The Apple Watch environment doesn’t allow many fun features.

Option 3: Focus on long-term metrics and impulse saving.

After identifying what kinds of behaviors we wanted to encourage, and learning what the watch environment allowed, we decided to focus on account balance, lifetime returns, and impulse deposits. This feature would allow customers to Force Touch (or press firmly) on any investment goal and choose an amount to deposit immediately from their wrist. The goal would then update instantly and customers could rest assured knowing their $200—or whatever amount—was safely invested and hard at work, rather than sitting idle in a checking account.

The verdict: The watch’s Force Touch feature would allow customers to invest on the spot.

How We Built It

Designing an app that satisfied customer needs and Apple Watch guidelines was only half the problem—we still needed to test the prototype on a device.

First, we sent a product designer and engineer to visit Apple HQ in Cupertino, Calif. to test on a couple of watches. We also pre-ordered our own development watch to conduct further testing before shipping the app.

This was a critical step in the process. Showing customer data of any kind on an Apple Watch is hard; each request for data must be routed from the watch, through the customer’s iPhone, to servers in the cloud, back through the iPhone, and finally to the watch screen. Adding Betterment’s keychain security and options for TouchID and PIN authentication to that already-complex system introduced many new challenges.

However, after weeks of planning, a full day of testing at Apple HQ, and a few more days back at the office after our watch arrived, we were able to ship a great new app that empowers customers to help keep their investment goals on track right from their wrist.

This article was written with Andrew Mocny.

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