Guides
What to buy in Guides: articles, explanations and technology developments with context and verified sources.
The wattage printed on the box does not, by itself, guarantee that a charger will work at the expected speed. Learn how to compare your device, charger, ports, and cable before you buy.
A practical checklist for comparing condition, battery, seller and return terms when buying a refurbished phone, without confusing commercial warranties with legal rights.
How to choose a CO₂ monitor: which sensor specifications are documented, how to interpret indicative thresholds, and which limits should not be mistaken for household targets.
How to choose a smart lock with Matter and Thread, check the physical fit, and distinguish source-backed facts from features that depend on the model, platform, and installation.
Practical criteria for choosing and documenting a power bank for a phone and laptop: understand capacity, check the cables, and verify airline rules before flying.
How to choose a security key without assuming compatibility: what to check across your accounts and devices, how to assess connectivity and certifications, and why it is worth planning a backup option before relying on a key.
How to choose a NAS that enables true 3‑2‑1: which CPU and RAM Btrfs or ZFS need, how many bays you need today and tomorrow, why 2.5GbE helps, what immutable/WORM snapshots imply, how to encrypt folders or volumes, and how to verify real S3 (Backblaze/Wasabi) and Glacier support, plus UPS and Time Machine over SMB.
