SkyKeys won't connect?

Work down the list; the first three solve most problems.

1. SkyKeys Console is running on the Mac. Its icon is in the menu bar (top right). Not there? Open it from Applications. Not installed? See the apps.
2. SkyKeys is open on the iPhone, and the iPhone is unlocked. A locked phone can't keep a connection open.
3. The iPhone is connected to the Mac. SkyKeys Console › Devices (menu bar › Devices…) lists a new iPhone under Available with a 6-digit code and its name (like Happy Otter (iPhone 13)), and the iPhone lists the Mac the same way (SkyKeys: connection menu › Devices; SkyKeys Legacy: the dot › Devices…). Press Connect on either one, check that both show the same code, and press Connect on the other too. Not Now ends a request; either side can ask again. Nothing listed? Press Refresh on either side. Listed under Blocked? Unblock it first.
4. It isn't disconnected. "Disconnected on your Mac" on the iPhone: the Mac disconnected it. Click Connect on its card in Devices (or the menu bar › the phone › Connect). "Disconnected" after you tapped Disconnect on the iPhone: tap Connect there.

See how the connection is doing

On the iPhone, tap the connection icon in the dock (SkyKeys) or the dot (SkyKeys Legacy): each connection is listed with its strength and latency. Its colour shows it at a glance (green: good, yellow: fair, red: weak), and the iPhone tells you when the one in use gets weak: move closer to the Mac, or plug in. On the Mac, each phone's card in Devices shows every connection, with Use and Reconnect.

Several phones, several Macs

• The first time, both screens confirm a code. After that it connects by itself whenever SkyKeys is open and the Mac is in reach.
• Disconnect from either side, without unpairing: on the iPhone (connection menu › Disconnect) or on the Mac (Devices › Disconnect). The side that disconnected is the side that connects again.
• One Mac, many phones: all of them work at once, each with its own pages. Every phone has a name made up for it, so two of the same model are easy to tell apart; rename it on the phone or on the Mac.
• One phone, many Macs: it can be connected to each, but it controls one at a time: the one it's using, or the one you pick on it (Devices › the Mac › Use This Mac). The others can Ask to Use Here: the iPhone asks you. No Mac takes a phone over by itself.
• Forget (Devices, on either side) removes the pairing on both: the other side forgets too, and connecting again takes the code. Block refuses a phone (on the Mac) or a Mac (on the iPhone) until you unblock it.

Codes and encryption

• Connecting a phone makes a pairing key that only that iPhone and your Mac have (kept in each one's keychain). Every connection after that proves it, and everything between them is encrypted, so nothing else on your network can read it or pretend to be either of them.
• The code is how you know it's your iPhone and your Mac: compare it on both screens before pressing Connect. Neither side can connect the other on its own.
• A reinstalled phone, or one forgotten on one side while the other was away, connects again the same way: with the code on both screens.
• SkyKeys and SkyKeys Legacy 0.7.1 connect to a new Mac only with SkyKeys Console 0.7.1 or later: update the Mac first.

By cable (USB)

• Unlock the iPhone and tap Trust when it asks about this computer.
• Try another cable or port: some cables only charge.

By Wi-Fi

• The Mac and the iPhone must be on the same Wi-Fi network. Guest and some office networks keep devices apart.
• iPhone: Settings › Privacy & Security › Local Network › SkyKeys: on.
• Mac: System Settings › Privacy & Security › Local Network › SkyKeys Console: on. A VPN or a firewall blocking incoming connections can stop it too.

By Bluetooth

• Bluetooth on, on both. The first time, both ask to pair: on the Mac click Connect, on the iPhone tap Pair.
• Worked before but not now (pairing is out of date)? On the phone's card in Devices click Fix…. Or by hand: Mac System Settings › Bluetooth › the iPhone › ⓘ › Forget This Device, and the same for the Mac on the iPhone. Then open SkyKeys and accept pairing.
• iPhone: Settings › Privacy & Security › Bluetooth › SkyKeys: on. Mac: the same for SkyKeys Console.

Still stuck

• Quit and reopen both apps.
• On the Mac, SkyKeys Console › Settings › Phone › Diagnostics writes details to ~/Library/Logs/SkyKeys.log.
• Write to support@projectskykeys.com with what you tried, your iPhone model and iOS version, and your macOS version. Or use Send Feedback in the apps.