This is about as simple as it gets. You open the app, select your sex, type in your age, and type in your weight (can use either imperial or metric)...and INSTANT results. Again, I was amazed...no ads!!!! I have no idea why someone else gave this a 1-star review; they just rated it and didn’t say why they did that. For all I know that reviewer was disappointed because they didn’t have 3 trillion genders to choose from, or maybe they hate seeing that they’re actually obese when the app tells them what their BMI is. No clue. I do know though that this app is exactly what I was looking for. Kudos to the developer for making an app that will not spam me with endless ads. And, it delivers on its promises. Accurate, fast, reliable, and easy to understand. 5 Stars!!