AceSense FAQ — Accuracy, Privacy, Devices, Courts, Pricing
Real answers to the questions players ask: clay courts, doubles, GDPR, free tier, Android support, Apple Watch dependency, and more.
This page answers the questions we get most often, organised by topic. If your question isn't here, email us — and we'll add it.
Accuracy
How accurate is AceSense's shot detection?
Current build is roughly F1 0.92 forehand, 0.91 backhand, 0.88 serve, 0.83 slice, 0.78 volley on our held-out amateur test set. Volley is the hardest stroke because of net occlusion; volleys at the service line are sometimes confused with mid-court groundstrokes. We publish the full methodology and update the numbers each release on the accuracy page.
How accurate is the serve-speed reading?
Median error vs a Pocket Radar Smart Coach is roughly 6.2 km/h on first serves in our internal benchmark. We slightly under-read the radar on average by ~2 km/h (suspected cause: camera-distance estimation in the homography step; under investigation). Variance on the same server across 20 serves is typically under 8 km/h, which is meaningfully tighter than some field-reported AI tennis app numbers.
How does AceSense compare to Hawk-Eye?
It doesn't, fundamentally. Hawk-Eye uses 6-10 calibrated stadium cameras, runs in real time, and costs millions in fixed infrastructure. AceSense uses one phone-recorded video. We're not chair-umpire-grade and we don't claim to be. We're a coaching tool for amateurs (NTRP 3.0-4.5), not an officiating tool. The right comparison is to your coach's eye over four lessons, not to a stadium calibration system.
Privacy and GDPR
Where is my video stored?
europe-west1 (Belgium), Google Cloud. EU-hosted at every step of the pipeline. The video is uploaded to EU storage, analysed on EU GPUs (RunPod's EU region), and the report is stored in EU storage. After the report is generated you can delete the source video; the report stays. We don't move data outside the EU.
Is AceSense GDPR-compliant?
Yes. EU-hosted, EU-headquartered, with a documented privacy policy at /privacy. You can request a full data export (everything we hold on you, in JSON + the original videos as MP4) or a full deletion from the dashboard at any time. We don't sell or share your video with third parties. Subprocessors (Google Cloud, RunPod, our payment processor) are listed in the privacy policy.
Do you train AI models on my video?
Only with explicit opt-in. Off by default. The opt-in is a one-tap toggle in account settings, separate from the privacy policy click-through, and you can revoke it any time. Without opt-in your video is processed once, the report is generated, and the video is accessible only to you and anyone you share a report with.
If you opt in, your video joins the training pool that improves future model releases. We don't share opted-in training data with third parties either; it stays inside our model-training pipeline.
Devices and platforms
Does AceSense work on Android?
Yes. Built mobile-first for both iOS and Android. Pixel, Samsung, OnePlus, and any modern Android device with a 1080p camera works. SwingVision is iOS-only — see their own SwingVision Android update newsletter. AceSense was designed to fix that gap from day one.
Does AceSense work on iPhone?
Yes. iPhone 11 and later, iOS 16+. Tested extensively on 13 Pro through 16 Pro. iPad is supported but the phone form factor is what we optimise for — the camera and the upload UX assume a phone. See the iOS page for specifics.
What's the minimum phone spec?
Any phone that can record 1080p at 30fps in landscape. That's roughly iPhone 8+ on iOS and any Android from 2020+. Higher frame rate (60fps) is preferred but not required. We don't require a specific GPU on the phone — the AI runs in the cloud.
Do I need an Apple Watch?
No. AceSense runs entirely from your phone video. No wearable, no Apple Watch, no external sensors. SwingVision Pro Max requires an Apple Watch for real-time line calling; that's the strongest feature in their iOS-only stack and the main reason some players consider them. AceSense doesn't have an equivalent feature and doesn't require one — our analysis runs on the recorded video, not in real time on your wrist.
Court compatibility
Does AceSense work on clay courts?
Yes, with a dedicated clay-court keypoint model that handles the lower colour contrast of red clay. Bounce localisation median error is ~38 cm on clay vs ~22 cm on hard courts. The honest caveat: heavily kicked-up dust on long rallies degrades ball tracking through bounces, and clay matches with extended rallies will see slightly more interpolation in the bounce step. Detail on the accuracy page.
Does AceSense work indoors?
Yes. Indoor hard courts work at ~96% court keypoint accuracy in the current build. The main caveat is older halls with metal-halide lighting that flickers at mains frequency (50 Hz EU, 60 Hz US) — this can cause occasional ball-detection issues on fast shots. Modern LED-lit indoor halls are fine. If your hall flickers, set your phone's shutter speed manually to 1/120s (60Hz) or 1/100s (50Hz) using a third-party camera app.
Can I use AceSense on a public-park court with no fence?
Yes. Bring a 5-7 ft tripod and place it 6-10 ft behind the baseline. The fence is the easiest mounting solution but it's not required. The how-to-film guide covers the alternatives, including using a side fence at the centre line if the back fence is missing.
What if my court is small (junior / scaled-down)?
Junior courts (78 ft, scaled-down lines) are currently treated as full-size courts in the homography step, which skews bounce coordinates. Stroke-quality scoring works fine — that doesn't depend on court geometry. Native junior court support is on the roadmap for 2026 H2.
Pricing
Is the free tier really free?
Yes. 3 analyses per month, full report, no credit card. The free tier exists because we'd rather you test on your own matches before paying than buy blind. There are no watermarks, no feature gates within the report, and no time limit. See full pricing.
Do you offer refunds?
Yes — within 14 days of purchase, full refund, no questions. EU consumer law mandates this for EU customers; we honour it for non-EU customers too. Email [email protected] with your account email.
I'm switching from SwingVision (or PB Vision, or OnForm). Can I keep my history?
Reports themselves can't be imported — none of those tools have public APIs for export. But you can re-upload your past video files to AceSense and rebuild your timeline. The first 3 fortnights of fortnightly users typically fits in the Free tier; longer histories are easier on Pro. See the pricing comparison for cost detail.
Doubles
Does AceSense detect doubles?
Doubles is in beta as of February 2026. Aggregate shot mix, ball tracking, and heatmaps work fine. Per-player attribution on net exchanges (which player at the net hit which volley) is unreliable in the current build because pose detection drops in confidence when four players overlap from the camera angle. We document the current state on the accuracy page and don't recommend Pro purchases primarily for doubles use yet.
Sharing and coaches
Can I share my report with my coach?
Yes — one tap from the dashboard, generates a public read-only link that opens in any browser, no AceSense login required on the coach's side. Links expire after 30 days by default (configurable on Pro) and you can revoke them any time. The coach handoff guide covers the practical workflow including what to write in the message.
Can my coach see my video?
Optional. By default the share link contains the report only — six sections, browser-readable. On Pro and Team you can include annotated video clips alongside the report (2-second per-shot clips). Useful for serve work; less useful for full-match review where the report is faster to scan.
Setup and recording
What's the right phone position for filming?
Centred behind one baseline, 6-10 ft back, 5-10 ft high, in landscape, 1080p at 60fps. Above the net cord is the rule. Below 5 ft height = bad results. The full filming guide has every detail and the edge cases for fence-less courts and indoor halls.
Can I use AceSense with a GoPro or other action camera?
Yes — record on the GoPro, transfer the file to your phone, upload from the AceSense app. The caveat is that wide-angle lenses introduce barrel distortion that the homography step doesn't fully correct. Use a flatter lens setting (Linear, not SuperView) if your camera supports it. Phone cameras at the main 1× lens generally produce better AceSense results than ultrawide phone modes for the same reason.
Does AceSense need 4K video?
No. 1080p at 60fps is the recommended setting. 4K wastes storage and upload time without improving the analysis. We process 1080p input at full resolution; 4K input is downscaled internally to 1080p before the pipeline runs.
Still have a question? Email us. For deeper detail: How AceSense works · Accuracy methodology · Pricing · Examples · vs SwingVision
Frequently asked questions
- How accurate is AceSense's shot detection?
- Current build is roughly F1 0.92 forehand, 0.91 backhand, 0.88 serve, 0.83 slice, 0.78 volley on our held-out amateur test set. Volley is the hardest because of net occlusion. We publish the full methodology and update numbers each release on the accuracy page.
- How accurate is the serve-speed reading?
- Median error vs handheld radar (Pocket Radar Smart Coach) is roughly 6.2 km/h on first serves in our internal benchmark. We slightly under-read the radar on average by ~2 km/h. Variance on the same server across 20 serves is typically under 8 km/h.
- How does AceSense compare to Hawk-Eye?
- Hawk-Eye uses 6-10 calibrated stadium cameras and runs in real time on millions in fixed infrastructure. AceSense uses one phone-recorded video. We're not chair-umpire-grade and we don't claim to be. We're a coaching tool for amateurs, not an officiating tool.
- Where is my video stored?
- europe-west1 (Belgium), Google Cloud. EU-hosted at every step of the pipeline. After the report is generated you can delete the source video; the report stays. We don't move data outside the EU.
- Is AceSense GDPR-compliant?
- Yes. EU-hosted, EU-headquartered, with a documented privacy policy at /privacy. You can request a full data export or full deletion from the dashboard at any time. We don't sell or share your video with third parties.
- Do you train AI models on my video?
- Only with explicit opt-in (off by default). The opt-in is a one-tap toggle in account settings, separate from the privacy policy, and you can revoke it any time. Without opt-in your video is processed and then accessible only to you and anyone you share a report with.
- Does AceSense work on Android?
- Yes. Built mobile-first for both iOS and Android. Pixel, Samsung, OnePlus, and any modern Android device with a 1080p camera works. SwingVision is iOS-only; AceSense isn't.
- Does AceSense work on iPhone?
- Yes. iPhone 11 and later, iOS 16+. Tested extensively on 13 Pro through 16 Pro. iPad supported but the phone form factor is what we optimise for.
- What's the minimum phone spec?
- Any phone that can record 1080p at 30fps in landscape. That's roughly iPhone 8+ on iOS and any Android from 2020+. Higher frame rate (60fps) is preferred but not required.
- Do I need an Apple Watch?
- No. AceSense runs entirely from your phone video. No wearable, no Apple Watch, no external sensors. SwingVision Pro Max requires an Apple Watch for real-time line calling; AceSense doesn't have an equivalent feature and doesn't require one.
- Does AceSense work on clay courts?
- Yes, with a dedicated clay court detection model that handles the colour-contrast challenge of red clay. Bounce localisation median error is ~38 cm on clay vs ~22 cm on hard courts. Heavily kicked-up dust on long rallies degrades ball tracking through bounces.
- Does AceSense work indoors?
- Yes. Indoor hard courts work at ~96% court keypoint accuracy. The main caveat is older halls with metal-halide lighting that flickers at mains frequency, which can cause ball-detection issues on fast shots. Modern LED-lit indoor halls are fine.
- Can I use AceSense on a public-park court with no fence?
- Yes — bring a 5-7 ft tripod and place it 6-10 ft behind the baseline. The fence is the easiest mounting solution but not required. The how-to-film guide covers the alternatives.
- What if my court is small or scaled down (junior court)?
- Junior courts (78 ft) are currently treated as full-size courts, which skews bounce coordinates. Stroke-quality scoring works fine. Native junior court support is on the roadmap for 2026 H2.
- Is the free tier really free?
- Yes. 3 analyses per month, full report, no credit card. The free tier exists because we'd rather you test on your own matches before paying than buy blind.
- Do you offer refunds?
- Yes — within 14 days of purchase, full refund, no questions. EU consumer law covers this for EU customers; we honour it for non-EU customers too.
- I'm switching from SwingVision. Can I keep my history?
- Reports themselves can't be imported (no public API on SwingVision's end). But you can re-upload your past videos to AceSense and rebuild your timeline.
- Does AceSense detect doubles?
- Doubles is in beta as of February 2026. Aggregate shot mix and heatmaps work; per-player attribution on net exchanges is unreliable in the current build. We don't recommend Pro purchases primarily for doubles use yet.
- Can I share my report with my coach?
- Yes — one tap, generates a public read-only link that opens in any browser, no AceSense login required for the coach. Links expire after 30 days by default and can be revoked any time. The coach handoff guide covers the workflow.
- Can my coach see my video?
- Optional. By default the share link contains the report only. On Pro and Team you can include annotated video clips alongside the report — useful for serve work, less useful for full-match review.
- What's the right phone position for filming?
- Centred behind one baseline, 6-10 ft back, 5-10 ft high, in landscape, 1080p at 60fps. Above the net cord is the rule. The full filming guide has all of it.
- Can I use AceSense with a GoPro or other action camera?
- Yes — upload the file from your phone after transferring it from the GoPro. Wide-angle lenses introduce barrel distortion that can affect court detection; use a flatter lens setting if your camera supports it.
- Does AceSense need 4K video?
- No. 1080p at 60fps is the recommended setting. 4K wastes storage and upload time without improving the analysis. We process 1080p input at full resolution; 4K input is downscaled internally.