Here are my thoughts on the ini EFB's
I am going to compare the Last XP efb from the A300v2 to the Microsoft A310
Both EFB's have excellent ground handling pages that are easy to use and also great general weather pages.
However I think the MSFS A310 iteration falls flat with its performance calculator and weight & balance page. The XP efb had a great flow. Load sheet -> Set Weights -> Send to T.O Perf -> directs to T.O Perf Page -> complete T.O Performance. This was an excellent way to get a lot of the behind the cockpit work done. The T.O. Perf page itself was also incredibly intuitive. All the weights were set from the previous load sheet page and all the user had to do was set departure airport and pull metar. This is where I think the MSFS A310 is the most disappointing. Weights needed to be reentered, grab the metar (if the refresh metar feature didnt break, sometimes it lingers on old airports when full reset isnt pressed) and also runway data (length/heading) had to be entered manually or through a hidden autofill feature. Feel like this was a big fall compared to the XP user experience in that regard.
The MSFS A310 UI itself is actually really good to look at and navigate, the front end did a really good job designing it. I just hope some of the backend design choices can take a page from the XP version. I will counter and say there could have been some limitations due to trying to make it compatible on serval different platforms but I hope with the coming A300F a lot of the features that made the XP version so good can be reimplemented in the future. Like weights being sent to other pages, perf sent to FMS, etc and I really look forward to the next EFB to come to the ini family!