Clorox Spa 5-Way Test Strips

I believe I am supposed to read the strip right away, however, it is changing all the time so I have difficulty deciding what I actually need to add if anything. The app seemed interesting. I did try to follow the directions of the 5 star review but it won't allow the gallon amount it calculated when I put in the size. I image because it is too small. I would like to use an app, something to make this simple. We just got the hot tub in July and I am trying to make sure it stays clean. I would like some real clear directions. I recommend it because we need something to measure what is going on in the water. Perhaps there are better/clearer instructions available I haven't found anything else.

Bought these test strips to test spa water. Says "Pool & Spa" right on the box. App only tests pool water. Weird....for a brand like Clorox, I expect more.....maybe some product manager training or fix the graphics on the box. Fyi...testing spa water would literally take just a few lines more of code for your Android app. I'd help you out but I am retired and will mostly be laying around in my spa.