iris fuel 50 not able to download from playstore it is showing insufficient storage but i have big storage space in SD card iris fuel 50 not able to download from playstore it is showing insufficient storage but i have big storage space in SD card(2GB in internal memory and 29GB in sdcard but unable to download )
I think there're some solutions for you:

Uninstall the Google Play Store updates:


Open your Settings > Apps 
Find and select Google Play Store from the list  
On stock Android 6+, press the menu icon in the top right corner of your screen menu 
Press Uninstall Updates


Move large apps to your SD card

Get your apk file from PC and then transfer them to your device : There're variety of third party store like Download Apk file for PC for free .This site is safe and free of malware so don't worry. 
Hope these solutions can help!