There's only one good charger that has bluetooth with a mobile app, and that's the SkyRC MC3000. I have it, and, even though it's really good, it is roughly three times the cost of a "normal" good charger such as my Nitecore UMS4 that I use daily. The MC3000 is not new, it has been in existence for years, but this also means that firmware issues have been ironed out so, actually, in this instance I consider that a good thing... but in the end it's still pricey.
The app works well on my Huawei P30 Pro with Android Pie, it's nice to have, though not really necessary. For me, the main benefit is it lets me avoid using the clicky push buttons on the charger. After the charging starts, I turn my phone's bluetooth off again, put it in ultra power saving mode. The charger can do a loud (but optional) beep after a battery has finished charging so, there's no need to keep monitoring the app constantly all the time. Nevertheless, it is reassuring to know I can always have another quick peek when necessary.
The MC3000 is absolutely packed with advanced features, there's much more than the average user will ever need. Keeping the Advanced mode set to disabled is recommended with this charger if you don't know what you're doing, as some of these features definitely are not without risk.
The PC monitor software that works via USB connection is primitive and very limited in its capabilities, like, it doesn't let you edit or save any profiles. If you use this program to quickly launch the charging, pressing any button on the charger will interrupt the charging so that you'll have to re-launch the charging again after that. Using the app avoids this, but then you don't get to see nice graphs. The PC functionality part of this charger is limited to USB and can best be used with DataExplorer (third-party software). As a result from all that, you won't be using the PC a lot with this charger if you're not particularly interested in the high technicalities of battery monitoring and analysis.