For Starters Nexus 5 was able to run USB storage devices via third-party apps and other means but the device never had native support for USB OTG.
All Thanks to Android Marshmallow Update, with the Android 6.0 Marshmallow, it is changing. Now you can plug n play USB drives (with the FAT32 file system) into your Nexus 5 without any issues.
If you plug a USB drive with NTFS or other filesystems into your Nexus 5, it’ll ask you to format it and turn it into FAT32.
Also, the notification bar has nice switches to “EXPLORE” and “EJECT” the drive.
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