Just plain broken
Happy to pay money for something that works. Unfortunately this app for coffee extraction doesn’t. The back end calculation is simply off. My TDS is 1.15, my dose is 37.5 and my end brew weight is 514. Using a calculator you arrive at about 15.75% extraction, but the “tool” says 16.4%. This will make you a worse brewer. Also, you’re forced to set a LRR, instead of having this being a deliverable. You can’t adjust the water weight and the end beverage weight independently. These numbers are locked. Another flaw.
A Useful Tweak
One way in which VST could improve the app for some, while allowing a greater use, and being an industry leader once again, would be to allow for a hundredth place in the dosing. There are more scientific scales like the OHAUS SCOUT or the U.S. SOLID 5000g/0.01g being seen in the industry as coffee is increasingly looked to as a science.
With doses as small as 12g in pour overs and espresso, the difference of a tenth of a gram is nearly a percent of the mass. The difference between tenths of a gram in an extraction yield percentage reading is also considerable at around a quarter of a percent.
Of course most people brewing coffee are not currently using a scale with readings to the hundredth of a gram, but if the app allowed for such, there would almost certainly be an eventual increase in the amount of people who found it a useful tweak. After all, there are more brewers now who are aiming for previously unattainable levels of accuracy in their brewing and charting methods.
Just a sales tool
This app does very little beyond allowing you to buy plug-ins that cost significant money.
Liquid Retained Ratio
Coffee mode LRR.
Why it cannot be set to zero?
I think it could be set to zero.
Convenient and simple to use!
Update for iOS 11 please... wont even open now
Please update, thanks.
You cna get all this info on-line just google it. App is useless.
Worthless: description is false
This app only includes 'water mode'. If you want any of the other 'modes' (including coffee mode), you'll need to pony up another $30.00.
a very useful app . . .
and continually upgraded to be as accurate AND easy to use as possible. Every specialty coffee shop/roaster should be on the same page as VST.
Works great, but
UPDATED BELOW: The app has a slick interface and works great. I didn't even mind the charge for the module since I paid over $300+ for a refractometer. What irks me is having to shell out another $30 for to use it with my iPhone. The app is really just an iPhone app. While it will run on the iPad, it will not rotate. If I had know that fact I would have purchased the module for my iPhone instead. It will not allow one purchase to run on both machines... so I will be out $60 bucks if I want it on my iPhone. If it wasn't for that fact I would have given it five stars.
UPDATE: It just appears that you have to purchase the module twice. If you go ahead and select purchase, the app store states that you already purchased the module (app store logic flaw). Works great and fun to use.