Good and safe expense manager/tracker apps?

I have a detailed expense tracker excel sheet put on cloud that I can access (and fill) from my mobile. Idea is to add an entry to it the moment/or atleast some point in the day I do some transaction. The problem is I'm effing lazy when it comes to this.

So I am looking for an app that can help me create a monthly budget and also auto track my expenses and categorize them.

I'm cautious about security but I doubt if there is any app that will help me do this and not share my data. At this point I'm contemplating giving up on this criteria or build my own app.