I am on Android. It is called Timberlog. If you get it and have trouble, I can talk you through it. It calculates 'solid wood' volume. Not stacked splits volume. The "ft" is length of the round or log. I split to 16", so, if it's a round, I enter "1.333" for "ft." The "in" is for "inches" and it means diameter. The next blank is left to "1" if it's just one piece but if you have more than one piece the same size, you can enter "2" or whatever. Then it calculates the cubic feet of that piece. It keeps a running tally of the "session." You hit the "+" sign to add to the tally.
Bojan Zalar is the app creator of Timberlog. The app you found may be fine, have not tried it. Having capability to enter small end and large end diameter is superior. I have to average both ends.
I would have no problem throwing $40+ his way for fuel and time. My feeling is get in good with him and more wood will follow.
That is amazing. I have taken 2 loads from tree services before...not anymore; too much trash, slash, rotten wood, etc. I would take loads like yours all day long.