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Simulator Build

Simulator Build

There are 2 main types of simulators users may want to build. Each of these require less up-front acquisition of hardware and may be desirable as a first step towards becoming a Looper.

Please, review all the Intro and Build pages, even if you will not complete them yet.

Simulator using Browser Build:

  • No Mac computer required
  • Must have a paid Apple Developer ID ($99/year)
  • Must have a compatible phone

Follow the normal instructions to build with browser, install the app on a compatible phone and explore the app using the Pump Simulator, CGM Simulator or both.

Simulator using Build with Mac:

Build to a Simulated Phone on Mac Computer

This simulator requires access to a Mac or virtual computer, see Compatible Computer

  • Build pages to review, but complete later
  • Follow Xcode Version
  • Follow Xcode Settings but can skip the Add Apple ID section
  • Follow Build the Loop App but with the following variation:
    • Skip the section on Developer Mode (that is only when building to a phone)
    • Download the code as directed
    • Choose to Sign Manually in the Sign Targets section
    • Continue with the Build Free Loop page
  • Use the simulated iPhone that will appear on you Mac and set up the app as desired
  • This gives you a feel for the interface, but the simulator on the Mac has limitations

Build to a Compatible Phone

Build to a Compatible Phone using Browser Build

You don't need to do anything special when you build the app using the Build with Browser instructions. Install the app on your phone from TestFlight. Then select the CGM and/or Pump simulator desired. You must have a paid developer account.

Build to a Compatible Phone using Mac Build

When building to a real phone using a Mac, you must have access to a Compatible Computer and a Compatible Phone.

  • You can use a Free Apple Developer account
  • Follow Xcode Version
  • Follow Xcode Settings
    • If you have a developer ID, use it in the Add Apple ID step and follow the normal build directions
    • If you do not have a developer ID, use the Free Developer Account instructions in the Add Apple ID section
  • Follow Build the Loop App using the Free Account instructions
    • If your phone is running iOS 16 or newer, you must enable Developer Mode
    • Download the code as directed
    • Choose to Sign Manually in the Sign Targets section
    • Continue with the Build Free Loop page
  • Once the App is on your phone
    • Follow the set up the app instructions on your phone but choose a simulated pump
    • If you have a compatible CGM on this phone, you can select that or you can use the simulated CGM or enter glucose values on the main Loop screen

What to Expect with a Simulator

Locked Phone or App in Background

Loop will not work in the background without either a real CGM or a real pump to "wake" it up.

The app will only work in the background in these special cases:

  • Loop is on on the same phone as a CGM and you've added that CGM information to Loop
  • Loop is attached to a pump (Pod or Medtronic)
    • You can configure the pump to drip water (instead of being attached to your body)

In all other cases, the phone must be open and unlocked for you to test the app.

These CGM and pump options work to provide glucose readings or accept pump commands while the app is open, but will not "wake" the app when in the background or phone is locked:

  • Dexcom Share
  • Nightscout Remote CGM
  • CGM Simulator
  • Pump Simulator

Disable Notifications

When you have the Loop app on your phone to test as a simulator, you may want to disable notifications when you are not actively using it. Even if you quit the app, you will get Loop not Looping notifications while the app is on your phone.

To Disable Notifications:

  1. Tap on iOS Settings -> Notifications -> Loop
  2. Disable Allow Notifications

The Loop app, when open, will be quite aggressive at warning you that you have disabled Notifications, so you can reverse those directions to enable notifications when actually using the app.

Pump or CGM Simulator on Phone

The simulators for the Pump and CGM, with version 3.3 and later, hide their detailed configuration screen. The initial view is a demonstration screen showing a typical CGM or Pump display. In order to configure the simulator controls or delete the simulator, you must tap on the Simulator Settings row.

tap on simulator settings row to get to controls

If you do not see the Simulator Settings row, you have an older version. You can see the settings by doing a long-press (5 to 10 sec) in the top portion of the simulator screen. If you've counted to 10 and the display has not updated yet, then return to the main screen, go back to the simulator screen, and try again.

Delete the Pump or CGM Simulator on Phone

To delete a pump simulator or CGM simulator from the Loop app on the phone, you must first tap on the Simulator Settings row, see graphic above.

Then scroll down to the bottom of the screen and select Delete Pump or Delete CGM.

After deleting the simulator, you can then Add Pump or Add CGM.