How to Change Weight (iPhone)
You can easily change the weight from the log workout screen.
Just log a new workout and then tap the weight. You'll get a popup that allows you to change it. You can tap the weight itself there so the keyboard popups. You can enter whatever you want then with your keyboard.
Note that all weights include the weight of the bar because you lift it. So 100kg/220lb means a 20kg/45lb bar with 40kg/87.5lb on each side. If you tap the weight on the log workout screen it will show how much weight per side. Unlock StrongLifts Pro to see the plate calculator here with which plates to add and how much.
If you've trained before, best is to start with around 50% of what you could do for 5 reps. Do not make the mistake of starting too heavy. For more information, read these articles on the website...