Some forensic examiners found that they could retrieve even deleted data using "flasher" or "twister" boxes, tools developed by OEMs to "flash" a phone's memory for debugging or updating. However, flasher boxes are invasive and can change data; can be complicated to use; and, because they are not developed as forensic tools, perform neither hash verifications nor (in most cases) audit trails.[6] For physical forensic examinations, therefore, better alternatives remained necessary.