Guides, Tutorials & Technical Insights

Choose a guide by the stage that failed

Start with the task you actually need to finish. A nearby handoff, a remote recipient who is offline, and a group meeting require different workflows. The operating-system guides below show file selection and saving as well as networking. The architecture articles explain what our servers process. Comparison pages separate protocol differences from measured performance, because a product name alone cannot establish speed, resource usage, or privacy. These guides were reviewed against the repository on October 17, 2026; browser and network behavior should still be tested on your own devices.

If you cannot see the receiving device

Read the local Wi-Fi and WebRTC signaling guides first. Nearby discovery groups browsers by their public IP at our WebSocket service; it does not scan the local subnet or authenticate a nearby person. A VPN, cellular fallback, or guest-network arrangement can change the group. An explicit room gives you a shared invitation, but it still needs a reachable data path. Confirm the receiver's nickname and acceptance prompt before selecting private files. The Windows and Android guides include a small-file baseline you can repeat before changing network settings.

If devices appear but file data never starts

Move to the STUN/TURN guide and its troubleshooting matrix. Seeing a peer establishes signaling, while ICE determines whether a direct or relay route works. Guest AP Isolation can block local clients even though both browse the web. On Windows 11, review the active Public or Private profile and browser firewall permission, without disabling the firewall. On managed networks, ask for an approved route. A stored link is a different HTTPS path, and using it still needs to meet your organization's storage rules.

If a large transfer stalls or the saved file will not open

The large-file, iPhone, and Android articles cover foreground tabs, screen lock, available storage, and receiving-browser memory. Sending small chunks does not make the complete received Blob occupy a fixed small amount of resources. Keep originals until the saved copy is checked. Compare byte size and, for important archives, an independent digest. A video with unsupported codecs can fail to play even when its bytes arrived correctly. Record whether selection, connection setup, payload delivery, or saving failed before asking support to investigate.

If confidentiality or deletion is the main requirement

Read the AES-GCM, sensitive-document, and expiring-link guides together with the Privacy Policy. Direct WebRTC payloads use browser-to-browser DTLS and may traverse a TURN relay. Stored links pass through a Worker that handles plaintext and controls the encryption key; this is not zero-knowledge storage. Metadata and notes live separately in D1. Expiry and deletion remove service availability and stored records, not recipient copies. Independently encrypt files when operator access is outside your acceptable trust boundary, and verify the recipient through an appropriate separate channel.

How to use the performance worksheets

Tables labeled calculated examples are arithmetic scenarios, not hardware benchmarks. They divide a known payload by assumed capacities and explain excluded work. For your own comparison, hold devices, source bytes, network arrangement, and timing boundaries constant. Run three trials, record the median, identify direct versus relay paths, and verify the saved file. Measure process memory separately with a stated tool and sampling method. The Snapdrop and LocalSend references describe different deployments and protocols; they do not justify assigning universal speed or memory numbers to either product.

All fifteen topic guides and both comparison pages are static HTML, so their instructions are readable before the transfer application connects. Choose a non-sensitive test file when reproducing a problem and keep private download URLs, owner tokens, network addresses, and personal documents out of public diagnostic reports.