What Software Are You Missing?

As always, trying to do something meaningful with my life, please help me with your advice. I'm trying to plan a software development but I need to make sure that It will add value to people's life, as I don't like to develop and later find out that it don't add value.

So what simple software do you need or are you missing? That you don't mind paying for to save you time and make you more productive.

You can either PM me or reply here.

Thank you.