Sliding Explorer is a free to use file explorer for Android that does feature in app purchases, but they are only used for donations, the app is in full for free.
Ranked in these QuestionsQuestion Ranking
Pro Material Design
Sliding Explorer is designed following Google's Material Design guidelines.
Pro ZIP support
Sliding Explorer features ZIP file support for compressing and extracting .zip files.
Pro Root access
Sliding Explorer has root access support for editing root files on a device.
Con Has trouble reading external SD cards
Sliding Explorer has users reporting that there is trouble with it reading external SD cards.