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ANDROIDLOCATION · A GUIDE FOR UK LAWYERS Android Location: Fused Location, Wi-Fi and Cell Data How an Android Phone Works Out Where It Is, What It Keeps, and Why the Source of a Fix Governs Its Weight COMPUTER FORENSICS LAB

§ ABOUT THE AUTHOR PREPARED BY COMPUTER FORENSICS LAB E-DISCOVERY TEAM SOURCE, ACCURACY & CONVERGENCE CPR PART 35 EXPERT REPORT S FULL CHAIN-OF-CUSTODY DOCUMENTATION

§ CONTENTS In this guide 01 Executive summary 02 The problem in plain English: a fix is only as good as its source 03 How Android derives location: the fused model 04 Where Android keeps location 05 Accuracy by source: point, locality, area 06 Attribution, convergence and honest limits 07 Deployment: placing a phone in time and place 08 Source architecture: where else the evidence lives 09 Worked examples 10 Common mistakes and technical limitations 11 Questions to ask · Suggested wording 12 Checklist and red flags · When to involve a digital forensic expert 13 Frequently asked questions 14 Glossary · References · Disclaimer · How a specialist laboratory can assist

§ 01 · ORIENTATION Executive summary The headline point: an Android phone fuses satellite, Wi-Fi, cell and sensor signals into a single location whose accuracy depends entirely on which signals fed it, and keeps that location in Google's Location History, the phone's caches, app databases, photo metadata and cell and Wi-Fi records, so the source of every fix must be established because it governs the fix's accuracy and weight, and a placement rests on sources converging.

§ 02 · FIRST PRINCIPLES The problem in plain English: a fix is only as good as its source

§ 03 · THE F USED MODEL How Android derives location: the fused model GNSS WI-FI CELL SENSORS FUSED + ACCURACY