If their intent is to work me up to five minutes - great. As written, the app congratulates me after 40s and says, "Congratulations. You have good lung capacity." If I were only able to hold my breath for 40s I would be deeply concerned and not congratulating myself.
My take on their message, "Hey, we're making an app that helps boost your health with quick 5-minute activities." is that I'd receive something like a meditation + breathwork + gratitude journaling app which, in sum, accounts for five minutes of activity, not that their intent was to increase my lung capacity to five minutes.
The average person can hold their breath for 30–90 seconds. This time can increase or decrease due to various factors, such as smoking, underlying medical conditions, or breath training. So that's why we took a 40 seconds test (as an average) and congratulate you.
My take on their message, "Hey, we're making an app that helps boost your health with quick 5-minute activities." is that I'd receive something like a meditation + breathwork + gratitude journaling app which, in sum, accounts for five minutes of activity, not that their intent was to increase my lung capacity to five minutes.