I use a pretty good app, it’s called Dario, I have their smart meter that plugs in to my iPhone. It’s a fantastic piece of kit. Been using it for just over 2 and half years now. Advanced therapeutics distributes here in the U.K. comes from Israel, the home of some really good D research in my book as well.
I can log everything, insulin, food, exercise, mood, notes. Have it linked up to people to send them reports. it’s also syncs up to HealthKit, I imagine it does the same for Android if that has an equivalent.
The meter itself is as small as the tip of my finger, in the tiny little device in the picture is my strip holder and lancet device.
I also used the MyFitnessPal to get carb counts when structuring my meals plans. Take some readings with a pinch of salt, if it looks like it’s not right go to one of supermarket sites online and have a quick check. It’s usually spot on though.