FAQ (Frequently Asked Questions)

  • I’m pointing my camera at the red outline with gray cells, and nothing happens!
    You must press the screen of the camera to initiate a capture (the entire screen acts like a big shutter button). Then the cells (aka tiles) that are entirely on the screen will fill with gray. When all the cells have been filled, SASHA will start computing your result.
  • All my gray cells (aka tiles) have turned gray, but nothing happens?
    There are two possibilities.
    You may not really have captured all the tiles. Look in the lower right hand corner of the screen and you might see something like “captured: 174 out of 175”; this means there is still one tile that has not been captured. The other hint is that the red outline and the tiles move when you move the camera. The missing tiles are usually hiding along the red edges, especially near the right or left end. Also, remember that a tile cannot be captured unless it is entirely on the screen. Tile fragments will not capture.
    The second possibility, if your phone is slow, is that SASHA is working. If this is the case (e.g. on and old Nexus 5), the red outline and the tiles are frozen in place when the capture starts, but about 10-15 seconds later the a dialog box with a progress bar appears. You can then get a sense for how long the computation will take. Eventually, a “capture complete” message will appear.
  • I get “bad capture” messages?
    This happens some times on some devices. The exact reason is unclear, but it seems to be because the camera is overwhelmed in some way. Typically, if you slow down, give the camera a chance to catch its breath, you will stop getting the message. Other than the annoyance and confusion this message causes, it is harmless, and you can continue your capture process.
  • How fast is SASHA?
    It depends on your device. Just to give you a couple of examples, a Nexus 5 (2013) needs between 1 and 2 minutes to complete all the computations and give you a result. A OnePlus 6T(2018) takes 3-5 second for the same computations.
  • Are there instructions anywhere?
    Yes. There is a mini tutorial which is presented to you the first time you use SASHA. If you got impatient and skipped it, you can see it again by pressing the “?” in the upper right hand corner of the screen.
    There are more detailed instructions here.
    There is a video here; it is also reachable from the Google Play Store.
    When all else fails, read the instructions!
  • Is there a way to transfer SASHA’s computed results to my computer?
    Yes, a piece of paper and a sharp pencil with an eraser. 🙂
    I am planning to implement a shade map feature which would also allow data transfer. However, you will probably find pencil and paper preferable to holding your breath until I am done!
  • What are the device requirements to install and run SASHA?
    The formal requirement is an Android device with Camera, Magnetic, Gravitational, and Location sensors running at least API level 19. In practice, the age and capability of the device make a difference in terms of how quickly the app runs. The oldest device I have is a Samsung TAB3, and I find it painfully slow. I have a pixel 2 and 3a, which run reasonably well. My Pixel 3 is even better. My OnePlus 6T runs quite well.

    Except to send feedback via email, SASHA does NOT require internet or Voice; it is entirely self sufficient. You do not have to get a cellular plan, just the device. Of course, WiFi is helpful to install the app.

    Here is a list of devices to which users have downloaded SASHA, most common first:
    • Nexus 5X
    • A6013
    • Pixel 3
    • SM-G960U1
    • Pixel 3a
    • Pixel 5
    • Redmi 6A
    • SM-G960U
    • SM-G965U
    • Pixel 3 XL
    • SM-N960U
    • Moto Z2
    • SM-G965F
    • SM-N986U
    • SM-G950U
    • SM-G998U
    • SM-G986U
    • SM-G973U
    • SM-N986U1
    • E6910
    • SM-G960F
    • H932
    • Moto E
    • Moto E(4)
    • Pixel 4a (5G)
    • SM-N981U
    • LM-G820V
    • Moto G Power
    • Pixel 4a
    • Pixel XL
    • SM-G981U
    • SM-G981U1
    • SM-T700
    • VS986
    • XT1789-05
    • BAH2-W19
    • E6820
    • KB2007
    • LM-V600
    • LM-X220PM
    • M2007J17G
    • Mi MIX 3 5G
    • Moto G7 Plus
    • One 5G UW
    • Pixel 2
    • Pixel 4
    • Pixel 4 XL
    • SM-A217F
    • SM-A516U1
    • SM-G930V
    • SM-G950F
    • SM-G955U
    • SM-G977U
    • SM-J737V
    • SM-N960U1
    • SM-N975U
    • SM-T210R
    • XT1021
    • H918
    • Moto G7 Power
    • SM-G970U
    • SM-G970U1
    • SM-G991U


  • Why do I get an error when connecting to the web site?

Depending on your browser and it’s set-up, you may get an error similar to the following:

This error indicates that the security certificate is not valid. This is a known issue. Seeing as you will be doing nothing on the website which requires security, it is considered a low priority, albeit an annoyance. You can ignore this error.

You may also get errors warning you that your connection is not secure (encrypted). This is also a known issue, and can be ignored just as the above error.

In either case, you should be able to tell your browser to ignore these errors for this site.