How-to & troubleshooting

1. Get fobs

We recommend NXP NTAG213 fobs. Order from GoToTags or ShopNFC. One fob per client.

2. Assign fobs to clients

Go to Clients, open a client profile, then open the Fob Assignments panel. Tap “Assign new fob” and scan or enter the fob UID. The client can now use that fob to check in.

3. The scan flow

Open the Check-in Kiosk at /scan on a phone or tablet. When a client taps their fob (Web NFC on Android Chrome) or scans a printed QR code, the platform looks up the fob UID, verifies the client against their active package, decrements one session, and logs the check-in timestamp.

What happens when a package is depleted

If the client has no sessions remaining, the scan screen shows a “No remaining sessions” message and does not decrement. The coach is notified via the dashboard. The client keeps their fob — it becomes active again when a new package is assigned.

iOS caveat

Web NFC is only supported on Android Chrome. On iOS, use the QR fallback: print the per-client QR from their profile and have them scan it with the Camera app.

Opening the review screen

Client profile → Sessions → select a session → “Review & annotate” under a video thumbnail. The review screen opens with the video paused at frame 0.

Drawing tools

The toolbar has four tools: Line, Arrow, Circle, and Square. Select a tool, then click-drag on the video to draw. Color picker and stroke width are in the toolbar. Undo removes the last stroke.

Stroke-path presets

Below the toolbar is the presets bar with four one-click shapes: Topspin, Slice, Flat, and Kick serve. Each drops a Bézier curve approximating that ball-flight path onto the frame. Drag the handles to adjust.

Saving and sharing

Click Save annotation to write the drawing data to the session record. The annotated frame is visible to the client in their Student PWA. Click Export frame to download a PNG for sharing externally.

How to use it

During any open session, tap the mic icon in the session notes panel. Speak naturally — the transcript appears in real time. Tap the mic again to stop. The transcript is appended to the session notes field and auto-saved.

Browser support

Fully supported on Chrome (desktop and Android) and Safari 15+ (iOS/macOS). Firefox does not support the Web Speech API — the mic button will not appear. Edge on Windows works via Chrome’s engine.

On Chrome, audio is processed by Google’s speech service — only the resulting text transcript is stored in Session for Tennis. Audio never leaves your device or reaches our servers.

Where notes live

Voice-dictated text is stored alongside manually typed notes in the session record. Both appear in the client’s session history and are visible to the client in the Student PWA.

Specs

• Max duration: 60 seconds
• Max resolution: 720p (1280×720)
• Format: H.264 / MP4 (auto-compressed client-side)
• Bitrate: 1.5 Mbps target

How to upload

Open a session → tap the video drop-zone or camera icon. On desktop, select a file. On mobile, you can record directly or pick from the camera roll. The file compresses in-browser before uploading — you’ll see a progress bar during compression and upload.

iPhone notes

iOS Safari does not support SharedArrayBuffer, which is required for in-browser ffmpeg.wasm compression. On iPhone, the raw file is uploaded and re-encoded server-side via a Firebase Cloud Function. Upload may take slightly longer on iOS.

Creating a group session

Group Lessons → New Group Session. Set title, date, time, capacity, price per seat, and minimum seats. Save. The session is in “Pending” state until the min-seat threshold is reached.

Enrolling and dropping clients

Open any group session → Roster tab. Search for a client and click “Enroll.” To remove, click the X next to their name. The session auto-confirms when enrolled count reaches the minimum. Enrollment after the minimum is reached adds to the roster immediately.

Min-seat threshold

If minimum seats are not filled before the session date, you can manually confirm anyway or cancel. Cancellation sends a notification to enrolled clients.

Inbox

All client conversations appear in Messages (sidebar). Each client has their own thread. Conversations are sorted by most recent message. Unread counts appear in the sidebar badge.

Digest timing

Students receive a daily email digest of coach messages at 7 AM PT. They cannot reply in v3.0 — student replies are a v3.1 feature.

Student read-only (v3.0)

In the current release, students view messages in the Student PWA but cannot send replies from the app. All student communication in v3.0 flows through the email digest. Direct student reply is on the v3.1 roadmap.

Magic-link sign-in

Students authenticate via email magic link — no password. From a client profile, click “Send student invite.” The client receives a sign-in link. On first click, their Supabase Auth account is created and linked to their client record by email address.

Installing on iOS

On iPhone: open tennis.jkcreative.store in Safari → tap the Share icon → “Add to Home Screen.” The app icon appears and runs in standalone mode. iOS does not show an install prompt automatically — direct students to these steps.

What students can see (v3.0 scope)

• Their session history and notes
• Annotated video frames from their coach
• Messages from their coach (read-only)

Students cannot book, pay, or reply to messages in v3.0.

Inviting sub-coaches

Academy → Coaches → Invite Coach. Enter their email. They receive a 7-day invite link. On acceptance, they sign in with Firebase Auth and are added as a sub-coach under your account.

Seat billing

Your Championship plan includes 5 coach seats. Additional seats are billed at $25/seat/month, added to your next Square subscription charge. Current seat usage is visible on the Academy → Coaches page.

Roster assignment

Academy → Coaches → select a sub-coach → Roster. Add or remove clients from their roster. Sub-coaches only see clients assigned to them — not the full academy roster.

Plan pricing

Deuce $20/mo. Advantage $65/mo or $680/yr. Championship $125/mo or $1,310/yr. Annual plans save ~13%.

• Annual billing is a single payment at the start of each year.
• Monthly billing renews automatically until you cancel.

Upgrading or downgrading

Go to Billing in the sidebar. Upgrades take effect immediately. Downgrades apply at the end of the current billing period.

Migrating from CoachNow?

We have a step-by-step migration guide for moving your student list, lesson history, and notes. Email tennis@jkcreative.store to request it.