Safe Data-Wipe
The day will come: your good-old Android shall get replaced by a newer model. If you no longer need the "old one", you probably want to give it away. But you certainly don't want the new owner accessing your sensible data which might have been stored on it. So what to do?
There's of course the Factory-Reset. But does it really sanitize your data in a way they cannot be (easily) restored? Unfortunately, that's not the case: though they are deleted, they are not wiped – so with the right tools, they could be restored. Admitted, that takes some little knowledge and work – but it's possible. A good counter-measure is to really "nuke" or "wipe" the storage – i.e. overwrite it with "random patterns". Corresponding guidelines are described by the National Institute of Standards and Technology (NIST) in a PDF Dokument.
Secure Wipe
- Data Eraser - iShredder (4.5@9,181) Ǥ 12

free version sanitizes free space only - Data Sanitizer (4.4@38) 3
2
LastUpdate: 2020-10-04 free space only - Shreddit - Data Eraser (4@8,563) Ǥ 14

1 
- Remo File Eraser (4@247) 2

LastUpdate: 2015-09-13 - Secure delete (3.9@3,979) 4
LastUpdate: 2022-03-08 files + folders - SDelete - File Shredder (3.9@977) 5

1
LastUpdate: 2023-05-23 / SDelete Pro - File Shredder (5@13; ~EUR 2.75) 2 
LastUpdate: 2023-05-23 - Andro Shredder (3.7@1,863) 5
1
LastUpdate: 2018-03-20 files + free space - Wipe files (3.6@15) 2
LastUpdate: 2016-02-22 Github; securely wipes files (but not free space) - Android Data Eraser App (3.2@2,648) Ǥ 12

demo limited to 10MB/day; unlock key required (cost unknown) - Safe Delete (3@241) Ǥ 16
2
LastUpdate: 2020-02-05 safely deletes files (not wiping free space) - Photo Recovery - Data Recovery (2.9@2,540) Ǥ 15

12

- Secure Wipe (2.7@2,542) 1
LastUpdate: 2014-06-13 sanitizes free space only - Extirpater (0@0) 0
GitLab
Automated Deletion
Not quite a safe wipe as described above – but still a welcome helper: automatically do a factory-reset / delete all files, if the number of unsuccessful unlock-trials exceeds a certain threshold. That at least makes it more difficult for the attacker to access your data. Unfortunately, none of the few apps in this group is available anymore.
- Wasted (4.2@42) 4

LastUpdate: 2022-09-02 Github; wipes device when receiving broadcast message with authentication code - Ripple: respond when panicking (4@210) 0

Github; trigger panic actions in supporting apps - CleanSlate (0@0) 7
Github; remote wipe of an e.g. lost/stolen device
De-Deletion (Recovering)
- Dumpster: Photo/Video Recovery (4.3@703,410) Ǥ 21

10
a recycle bin - Fast Recovery : Photo & Video (4.2@31,753) Ǥ 22

13

- DigDeep Image Recovery (3.8@361,724) Ǥ 14

5

- Deleted File Recovery (3.5@54,723) 7

6

- Recover Deleted All Files, Photos, Videos &Contact (3.5@1,137) 11
4
LastUpdate: 2021-03-04 - DiskDigger photo/file recovery (3.4@517,172) 6

1
/ DiskDigger Pro file recovery (2.9@4,340; ~EUR 3.25) 6 
1
Intro 7/2019 - File Recovery - Recover Deleted Files (3.4@19,483) 7
3
LastUpdate: 2021-02-19 - File Recover : Photo Recovery (3.1@8,233) Ǥ 10

4
LastUpdate: 2024-09-28 - Recycle Bin (3@17,272) Ǥ 19

6
LastUpdate: 2024-01-15 - Photo Recovery: Video & File (2@14,940) Ǥ 7

10

Further Readings:
- 5 Best Ways to Permanently Delete Android Data (7/2022 - 7/2023)
- 5 Android Apps That Recover Deleted Files for You (5/2021)
- Best Apps To Delete Unwanted Photos from Android Phones Parmanently (8/2018)
- Handy verkaufen? Daten richtig löschen (12/2017 - 5/2022)
- Gelöschte Bilder wiederherstellen (3/2015 - 1/2019)
- Handy-Speicher voll? So könnt Ihr Euer Smartphone aufräumen (9/2014 - 4/2022)
- Android zurücksetzen: So macht ihr euer Smartphone komplett platt (10/2013 - 7/2023)
- Handy-Daten sicher löschen (10/2013 - 1/2018)



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