Eventually a simple word file could be enough. You just need to downwrite the info that is necessary to see patterns and learn about what you need to adjust. Screenshots can help as well, but again, no need to make thigns complicated, a simple folder with all that screenshots in enough, just don´t forget to make notes to the pics so you know what you did there when looking at it somewhen later
Yes, a simple word file is probably enough to document your trades, Most traders use spreadsheets to record their trades because as we see it is more likely organized than using a simple notepad to input the details. I don't document my trading activities but I think it is easier to use spreadsheets and it is more organized than having a word file with screenshots that is sorted into folders. This will vary depending on the user on which he is more comfortable using.
We do not need any apps or services that have payment to use so basically spreadsheet and excel are good to us in order to record our trades. I do recording in order for me to know if I'm in the right track or not, my record compose of win rate, the percentage and amount of my winning trade and losing trade, the date when I execute my trade, the strategy that I use and also the days when I hold it,
A simple spreadsheet with compose that I mention above is good especially if we want to know if we are improving as a trader. Documentation of our past trades are really important so basically we should also give time on it.