https://devrives.com/en/blog/ Notes from devrives, an independent software studio: product updates, open-data analysis, and development write-ups. en-US Sat, 10 Oct 2026 00:00:00 GMT https://devrives.com/en/blog/emergency-water-storage-per-person/ https://devrives.com/en/blog/emergency-water-storage-per-person/ Sat, 10 Oct 2026 00:00:00 GMT Store about 1 gallon (4 liters) of water per person per day, at least 3 days. A family of four needs 12 gallons. Tables by household size and storage tips. emergency water water storage emergency kit go bag disaster preparedness Safe-Life https://devrives.com/en/blog/wear-os-watchface-play-launch/ https://devrives.com/en/blog/wear-os-watchface-play-launch/ Fri, 02 Oct 2026 00:00:00 GMT What broke when we shipped a paid Watch Face Format app on Google Play: a dex file that must not exist, the Editable flag, two rejections. Wear OS watch face WFF Google Play AAB Android https://devrives.com/en/blog/korea-cctv-data-freshness/ https://devrives.com/en/blog/korea-cctv-data-freshness/ Thu, 01 Oct 2026 00:00:00 GMT Korea's national CCTV standard dataset mixes base dates from 2020 to 2026. We analyzed 378k records to see which regions publish fresh data. CCTV Open Data Data Analysis Korea Viewcone https://devrives.com/en/blog/korea-public-cctv-data-accuracy/ https://devrives.com/en/blog/korea-public-cctv-data-accuracy/ Tue, 29 Sep 2026 00:00:00 GMT Cleaning 380k rows of Korea's CCTV dataset revealed shared coordinates, cameras pinned to one spot, and install dates from 1899. CCTV Open Data Data Analysis Korea Viewcone https://devrives.com/en/blog/korea-public-cctv-by-region/ https://devrives.com/en/blog/korea-public-cctv-by-region/ Tue, 22 Sep 2026 00:00:00 GMT We aggregated Korea's national CCTV standard dataset by province. Regional camera counts, purpose breakdown, and how to read the numbers carefully. CCTV open data regional statistics data Viewcone https://devrives.com/en/blog/cctv-does-more-cameras-mean-safer/ https://devrives.com/en/blog/cctv-does-more-cameras-mean-safer/ Tue, 15 Sep 2026 00:00:00 GMT A meta-analysis of 41 CCTV studies found a 16% average drop in crime, but 51% in car parks and 7% in city centers. Why camera counts cannot measure safety. CCTV crime prevention neighborhood safety CCTV effectiveness Viewcone https://devrives.com/en/blog/how-to-request-cctv-footage/ https://devrives.com/en/blog/how-to-request-cctv-footage/ Tue, 08 Sep 2026 00:00:00 GMT How to request public CCTV footage in Korea: the request form, ID, subway cameras, the 30-day retention rule, the 10-day deadline, and reasons for refusal. CCTV footage request CCTV access Personal Information Protection Act Viewcone Korea https://devrives.com/en/blog/how-to-check-cctv-locations-near-me/ https://devrives.com/en/blog/how-to-check-cctv-locations-near-me/ Tue, 01 Sep 2026 00:00:00 GMT Find public CCTV locations in any Korean neighborhood on a free map of about 260,000 camera sites, and what to do if one is missing. CCTV location check neighborhood CCTV open data Viewcone Korea https://devrives.com/en/blog/flashlight-app-camera-permission-reason/ https://devrives.com/en/blog/flashlight-app-camera-permission-reason/ Fri, 06 Feb 2026 00:00:00 GMT No. On Android 6.0+, CameraManager.setTorchMode turns on the flashlight without CAMERA permission. Here is why some apps still ask. android.permission.FLASHLIGHT setTorchMode CameraManager android permissions camera permission flashlight app privacy Safe-Life app security emergency preparedness