Download iPadOS 9.3.5 (13G36) for iPad Air (WiFi)

You will have to note that you can only restore signed IPSW firmware files using iTunes or 3utools.

❌ This IPSW firmware is not being Signed by Apple

Firmware Identifier iPad4,1
iPadOS Version 9.3.5
Release Date 2016-08-25
Update Date 2016-08-20
Sha1sum
caa0fe07b6395ee4bd586b3e876ccc568d492d9f
Sha256sum
2693b36da3d575fc6128731319afa2b6dc31b8a3201eb4001bfd6d62d9b4b246
md5sum
0d922f13c1e553b0b8a89fcdf62c945c
Size 1.83 GB
FileName
iPad4,1_9.3.5_13G36_Restore.ipsw
Status

Download IPSW (1.83GB) Check device info
Release Notes

It should be noted that these are the official release notes for the from Apple

iOS 9.3.5 provides an important security update for your iPhone or iPad and is recommended for all users.

For information on the security content of Apple software updates, please visit this website:

https://support.apple.com/kb/HT201222