Also check if you have a stable internet connection on your smart device. Loss of connection will hamper the downloading of the app.
Please check if your smart device meets the minimum requirements for the Philips Treatment app. The App is supported by the following devices: iPhone 4S, 5, 5C, 5S or newer. iPod Touch 5th generation, iPad mini retina, iPad mini non-retina, iPad 3 retina, iPad 4 retina, iPad air. Newer devices than these are also supported. The device has to run on iOS7 or higher.
Also check if you have a stable internet connection on your smart device. Loss of connection will hamper the downloading of the app.