The Android PainChek app is 85MB and the iOS is 145MB download.
Assuming a download speed of 40Mbs (the average speed of a mobile connection in Australia as of mid-2017 as reported by http://www.speedtest.net/), the PainChek app should take around 15 to 20 seconds to download.
Even with a modest (10Mbs) connection, the App should only take around a minute to download.