You're right, totally missed from the screenshot and based my comment on the current App Store data.
I looked the app on Appannie (non paid account) and the pricing history is quite interesting:
26 Mar 2017 - 0.99 to Free
29 Mar 2017 - Free to 0.99
19 Jul 2017 - 0.99 to 1.99
20 Jul 2017 - 1.99 to Free
02 Aug 2017 - Free to 0.99
04 Feb 2018 - 0.99 to Free
10 Feb 2018 - Free to 0.99
03 Mar 2018 - 0.99 to Free
27 Mar 2018 - Free to 0.99
04 Dec 2018 - 0.99 to Free
03 May 2019 - Free to 0.99
05 Sep 2019 - 0.99 to Free
From the above details, it was a paid app for most of it's time. I wonder why the developer played with the pricing as much though?