What is crucial for you in a personal productivity app?

Hi hunters! I've been following new goal management apps for a while. Though having similar basic functionality, they offer different approaches and promote different features. I claim no fundamental research, I just summarized these "killing features" from my own experience. And it would be great to hear what is most important for you personally. Thanks for sharing a vote! P. S. If yours is not listed or you want to add something, I'll be glad to hear from you!