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

2019-11-24

Shreddit - Data Eraser (4.4@2,909) 8
Data Sanitizer (4.3@28) 4 LastUpdate: 2017-02-08 free space only
File Schredder (4.2@5) 5
Secure Erase with iShredder 6 (4.1@2,124) Ǥ 9 / iShredder™ 6 PRO Data Shredder (3.5@210; ~EUR 5.50) Ǥ 12 / iShredder™ 6 Enterprise Eraser (4.1@103; ~EUR 9.50) Ǥ 12 Video Review 10/2013; Intro 12/2013; Vorstellung 1/2014; free version sanitizes free space only
Phone Factory Reset (4@760) 2
Secure delete (3.9@3,668) 5 $Contains no known trackers \o/$ / Secure delete Pro (4.3@196; ~EUR 2.25) Ǥ 6 files + folders
Secure Bulldozer (Wipe Remove) (3.9@187) 4 LastUpdate: 2014-09-05
Safe Delete (3.9@90) 5 LastUpdate: 2018-04-02 safely deletes files (not wiping free space)
Fastwipe (3.9@85) 1 LastUpdate: 2014-03-18 sanitizes free space only
Safe Delete (3.9@47) Ǥ 17 LastUpdate: 2017-09-20 safely deletes files (not wiping free space)
SHREDDER : Data Eraser (3.8@432) Ǥ 10
FShred - Wipe Free Space (3.8@130) 2 $Contains no known trackers \o/$ LastUpdate: 2017-03-26 sanitizes free space
Secure Wipe (3.7@2,276) 2 $Contains no known trackers \o/$ LastUpdate: 2014-06-13 sanitizes free space only
Secure Eraser (3.7@986) Ǥ 7 LastUpdate: 2017-03-18 sanitizes free space only
cb Data Eraser (3.7@186) Ǥ 12 $Contains no known trackers \o/$ demo limited to 10MB/day; unlock key required (cost unknown)
Wipe Files (3.6@12) 2 $Contains no known trackers \o/$ LastUpdate: 2016-02-22 Github; securely wipes files (but not free space)
Andro Shredder (3.4@1,570) 6 LastUpdate: 2018-03-20 files + free space
SDelete - File Shredder (3.4@631) 4 LastUpdate: 2017-09-15 / SDelete Pro - File Shredder (3.1@10; ~EUR 2.00) 2 LastUpdate: 2017-09-17
Complete Wipe (3.4@101) 3 $Contains no known trackers \o/$ LastUpdate: 2014-07-03
Permanent Delete Files – Data Eraser (3.3@555) Ǥ 7
Secure File Deletion (3.3@72) 4 $Contains no known trackers \o/$ LastUpdate: 2013-04-29
Super Erase (3.1@457) Ǥ 5 files + folders; free space requires in-app payment (go pro)
Remo File Eraser (3.1@211) 2 $Contains no known trackers \o/$ LastUpdate: 2015-09-13

Automated Deletion

2019-11-24

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.

De-Deletion (Recovering)

2019-12-01

DigDeep Image Recovery (4.3@299,820) Ǥ 12
Restore Formatted SD Card (4.2@18,846) Ǥ 9
Recover My Files (4.2@8,977) 10
Restore Deleted Photos & Image (4.1@5,350) 4 LastUpdate: 2017-05-12
Recover Deleted Photos by Dumpster (4@274,889) Ǥ 23 Vorstellung 7/2014; Intro 7/2014; a recycle bin
Deleted Photo Recovery Workshop (4@60,330) Ǥ 8 $Contains no known trackers \o/$
GT Recovery - Undelete,Restore (4@39,218) Ǥ 17 $Contains no known trackers \o/$
Recover Deleted Files Photos & Videos (4@15,609) Ǥ 9 $Contains no known trackers \o/$
Recover Deleted Pictures (4@4,337) 5 LastUpdate: 2017-12-30
DiskDigger photo recovery (3.9@324,009) 5 / DiskDigger Pro file recovery (2.8@2,758; ~EUR 3.25) 5 Intro 7/2019
Recover Formatted SD Card (3.9@17,108) Ǥ 9
File Recovery - Photo & Video (3.9@11,622) Ǥ 5 LastUpdate: 2016-05-19
Recover Deleted All Files, Photos, Videos &Contact (3.9@407) 11
RECYCLING BIN (3.9@178) 8 LastUpdate: 2017-08-11
Data Recovery : Recover Deleted Photos (3.9@170) 10 LastUpdate: 2018-01-08
Recycle Bin (3.8@17,281) Ǥ 10
Recover All My Deleted Files (3.8@7,430) 4 LastUpdate: 2018-03-10
Undeleter Recover Files & Data (3.7@35,099) Ǥ 20 Intro 2/2012
GT SMS Recovery (3.3@2,471) Ǥ 10 $Contains no known trackers \o/$ LastUpdate: 2016-06-30
dr.fone - Recovery & Transfer wirelessly & Backup (3.1@28,676) Ǥ 6

Further Readings:

Best Apps To Delete Unwanted Photos from Android Phones Parmanently (8/2018)
Handy verkaufen? Daten richtig löschen (12/2017)
Handydaten sicher und endgültig löschen (9/2017 - 1/2018)
Gelöschte Bilder wiederherstellen (3/2015 - 1/2019)
Android bereinigen: So löscht Ihr überflüssige Dateien für mehr freien Speicherplatz (9/2014 - 12/2018)
Private Daten sicher löschen – so wird’s gemacht (7/2014)
Android zurücksetzen: So macht ihr euer Smartphone komplett platt (10/2013 - 1/2018)
Handy-Daten sicher löschen (10/2013 - 1/2018)

2019-12-01

IzzyOnDroid

Safe Data-Wipe

Secure Wipe

Automated Deletion

De-Deletion (Recovering)