It could be that the app developer(s) need to update their app(s) for correct use with iOS 8.3. You should contact the app developers. You can do this from the App Store. Find the app in question, select the app's "Details" tab, then scroll down to the section "Developer's Website" and click on whatever link is supplied and follow through to contact the developer.
Also read the reviews for the app in question...usually if an app is not working after an iOS update, the reviews will reflect that and will validate your findings. If the app is at fault, you'll have to wait for the developer to correct the issue. When reading the reviews, sort them by "Most Recent" to get the most recent reviews.
An additional step may help but you'll lose any app settings, progress, etc. That step is to delete the app from the device, then reinstall it from scratch. It may or may not help so you'll risk losing settings, progress, etc to test if it will help.