CruxCoach

Kilter Board climbing app for Android. Open source. Privacy-first, you own your data. Nostr-powered.
Zapstore: https://zapstore.dev/apps/com.cruxcoach.android
Source: https://codeberg.org/CruxCoach/CruxCoach

Public Key

npub1uadpshqpn5ysf82lev8zngkvn07szmkq7mvf9lyc7ml7qxq6fqxsmrqt2s

NIP-05 Address

cruxcoach@npub.cash

Profile Code

nprofile1qqswwksctsqe6zgyn40ukr3f5txfhlgpdmq0dkyjljv0dllqrqdysrgpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dswat2yu

Publishing to

offchain.pub

relay.damus.io

nos.lol

Author Public Key

npub1uadpshqpn5ysf82lev8zngkvn07szmkq7mvf9lyc7ml7qxq6fqxsmrqt2s

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Last Notes

2026-05-10 18:10:01 UTC

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Totally agree! Bouldering outdoors is a completely different vibe. But if you want to train for your outdoor projects, you might wanna try @nprofile…8teg, which is my Nostr native Kilter board app 😉

2026-05-10 17:57:41 UTC

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What happened to this project @nprofile…9s8u ? Did you release it and is it still in use? I developed an alternative Kilter board app @nprofile…8teg using nostr as it's backbone. Maybe we could have synergies?

2026-05-10 17:45:46 UTC

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Da ihr im neuen Podcast erwähnt habt, dass diese Folge nicht so gut bei euren Zuhörern ankam: Für mich war die Folge bisher eine der Highlightfolgen von euch.

2026-05-10 17:40:04 UTC

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Vielen dank an euch und natürlich auch @nprofile…vcku, @nprofile…en87 und @nprofile…ejmy für das spannende Gespräch und dafür, diesem wirklich coolen Projekt eine Plattform zu bieten! Ich werde es leider nicht schaffen, mir 6 Wochen freizuschaufeln, aber ich bin gespannt, was aus der neuen Kohorte wieder an Projekten rauskommen wird.
Und ich bin gespannt, ob/wann sich Souvereign Engineering tatsächlich dezentralisieren kann. Bei einer Souvern Engineering Alps Edition wäre ich auf jeden Fall dabei😉

2026-05-05 13:05:42 UTC

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Looking forward to it :)

2026-05-03 17:16:39 UTC

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Nice chalk bag 🐇

2026-05-02 17:23:50 UTC

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If you are a climber, give @nprofile…8teg a try

2026-05-01 16:10:06 UTC

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Good point. I guess YouTubers should be able to mirror their own videos to Blossom with one click. And auto-upload to Nostr when they post new videos on YouTube.
Of course it would be great, if we have much more videos on nostr, but I guess it would be to expensive to mirror just more or less all videos. Would be interested in your opinion on how well Nostr/Blossom scales regarding data growth.

2026-04-30 23:03:39 UTC

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Trying to do the same with the official Kilter Board App, I am trying to provide a better alternative to. At least sync from the offical app to CruxCoach/Nostr and opt in sync from CruxCoach to the official Kilter App if the user does not want to leave the old world completely.

2026-04-30 21:21:44 UTC

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Thats great to hear!

2026-04-29 18:09:04 UTC

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Thanks for the mention!

2026-04-27 17:10:10 UTC

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If you're still on the #bouldstr grind, give CruxCoach a try. Open-source Android app for the Kilter Board, building it right now.
Nostr side already has a few things going: identity via Nostr keypair (no account, no email), board database distributed over Blossom (content-addressed, verifiable), Zapstore distribution, and in-app dev contact via encrypted Nostr DMs. Encrypted Backup of User data via Blossom. All opt in. You can use it fully offline after the initial downloads, if you want to.
Feature requests, bug reports, ideas all very welcome.
Zapstore: https://zapstore.dev/apps/com.cruxcoach.android
APK Releases: https://codeberg.org/CruxCoach/CruxCoach/releases

2026-04-27 12:39:29 UTC

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2026-04-27 12:37:20 UTC

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2026-04-27 12:30:19 UTC

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Enjoying your climbing videos, mate! You might wanna give CruxCoach a try. Open-source Android app for the Kilter Board, building it right now. Maybe support for other boards in the future.
Nostr side already has a few things going: identity via Nostr keypair (no account, no email), board database distributed over Blossom (content-addressed, verifiable), Zapstore distribution, and in-app dev contact via encrypted Nostr DMs. Encrypted Backup of User data via Blossom. All opt in. You can use it fully offline after the initial downloads, if you want to.
Feature requests, bug reports, ideas all very welcome.
Zapstore: https://zapstore.dev/apps/com.cruxcoach.android
APK Releases: https://codeberg.org/CruxCoach/CruxCoach/releases

2026-04-27 12:28:06 UTC

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If you're still on the Kilter, give CruxCoach a try. Open-source Android app for the Kilter Board, building it right now.
Nostr side already has a few things going: identity via Nostr keypair (no account, no email), board database distributed over Blossom (content-addressed, verifiable), Zapstore distribution, and in-app dev contact via encrypted Nostr DMs. Encrypted Backup of User data via Blossom. All opt in. You can use it fully offline after the initial downloads, if you want to.
Feature requests, bug reports, ideas all very welcome.
Zapstore: https://zapstore.dev/apps/com.cruxcoach.android
APK Releases: https://codeberg.org/CruxCoach/CruxCoach/releases

2026-04-27 12:26:45 UTC

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2026-04-27 10:44:13 UTC

CruxCoach v0.1.3 just shipped — Nostr backup is now live!
Backup your climbing history and restore on new devices, end-to-end encrypted:
- 🔐 AES-GCM blob on Blossom
- 📍 Kind 30078 pointer (NIP-44 self-encrypted)
- 🔑 Your `nsec` is the only key to restore the backup
No accounts. No provider lock-in. Restore anywhere.
Also in this drop:
- ⚡ Quick-Send: 1-tap connect → send → auto-disconnect
- 🧗 Multi-frame routes play correctly again

2026-04-25 19:40:14 UTC

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Congrats on the rewrite!
For those shipping Android apps from a NIP-34 repo to @nprofile…gsu4 What's the current best practice?
As far as I can tell `zsp` doesn't auto-detect `nostr://` / gitworkshop URLs yet, so the options seem to be: point `repository:` at the underlying git server (Gitea/Forgejo/Codeberg) or just hand `release_source:` a direct APK URL.
Is that the right path? Any plans to make nostr-native repos a first-class source? 👀

2026-04-24 12:59:27 UTC

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I did not feel to much effect for bouldering. But might try it again in the future. With climbing there is always the strength increase vs weight increase dilema...

2026-04-24 10:08:16 UTC

The official Kilter Board app requires Google Play Services. It ships with Firebase Analytics, a Google Places API key, and a mandatory Kilter Board cloud account just to browse climbs.
CruxCoach ships with zero Google dependencies.
• Runs natively on GrapheneOS, CalyxOS, LineageOS, /e/OS
• Board data via Nostr + Blossom, not cloud sync
• No accounts, no telemetry, no tracking
• Works offline after initial database download
@Zapstore:
zapstore.dev/apps/com.cruxcoach.android
APK:
codeberg.org/CruxCoach/CruxCoach/releases/download/v0.1.2/CruxCoach-v0.1.2.apk
#kilterboard #climbing #degoogle #GrapheneOS #privacy #nostr

2026-04-24 07:54:58 UTC

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Nice project! CruxCoach has quite a lot in common with your pulsetto app. I was also annoyed that they force you to log in and stay online all the time and had to do some reverse engineering to reconstruct the BLE communication with the climbing board.

2026-04-23 14:55:52 UTC

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Users can create Feature requests/Bug reports/ just use the dev Chat in the App itself. I am using Nostr DMs just in the backend zu recieve and answer the user feedbacks. So the user does not need a separate costr client.

2026-04-23 09:58:40 UTC

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Thanks for the mention! Climbing app on the surface, but Nostr is most of the plumbing underneath:
• Keypair identity — no accounts, no email
• NIP-17 encrypted DMs for bug reports + feature requests, right from the app
• Blossom for distributing the public 85k-climb database — your ascents and logs stay on device
Encrypted cross-device backup over Nostr is on the roadmap. Zapstore was a natural fit. Feedback and Feature Requests always welcome.

2026-04-23 09:34:15 UTC

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I was a read-only Nostrich for quite a long time before starting to use it for CruxCoach. So I was already familiar with Zapstore by the time I wanted to publish the app.

2026-04-22 22:24:43 UTC

CruxCoach 0.1.2 is here
— In-app auto-updater
— Reliable notifications on aggressive OEM
— Share the app with nearby climbers via QR
Open-source, Nostr-native, you decide where your data goes.
@Zapstore:
https://zapstore.dev/apps/com.cruxcoach.android
APK:
https://codeberg.org/CruxCoach/CruxCoach/releases/download/v0.1.2/CruxCoach-v0.1.2.apk
#kilterboard #climbing #bouldering #nostr #android

2026-04-19 10:02:52 UTC

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Kilter Board climbing app for Android. Open source. Privacy-first, you own your data. Nostr-powered.

2026-04-16 18:41:50 UTC

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Well that makes two of us 🤝 Now we just need to clone ourselves at the board.
Actually, there's a path for that without Zapstore in the loop: v0.1.1 ships Local App Share — your phone becomes a WiFi hotspot + download page, your climbing partner scans two QR codes and has the app + the full 137 MB Kilter DB in under a minute. Zero internet, zero gatekeepers.
Full guide 👇
#nevent1q…xs7t

2026-04-16 17:25:12 UTC

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📱 How to share CruxCoach locally — zero internet required:
1️⃣ Settings → tap the share icon in the top right.
2️⃣ Pick "Share locally (WiFi Direct)". Your phone opens a
local hotspot + download page. Nothing leaves the gym.
3️⃣ The other person scans QR #1 to join your hotspot, then
QR #2 to open the download page.
⚠️ Turn mobile data + VPN OFF on the receiving device,
otherwise traffic won't route through the hotspot.
4️⃣ Download & install the APK (allow "Install from unknown
sources" if prompted). Then tap the green import button on
the download page — the app opens and imports the 137 MB
Kilter DB straight from your phone. No second download.

2026-04-16 17:22:28 UTC

🪨 CruxCoach v0.1.1 is out!
Headline fix: Local App Share now works end-to-end.
No internet. No Play Store. No app-store gatekeepers. No data
plan. Your phone becomes a WiFi hotspot + local download page —
hand the app (and the 137 MB Kilter climb database) to a mate
at the board in under a minute. Perfect for gyms with zero
reception, trips abroad, or onboarding a new climber on the spot.
In 0.1.0 the receiving device couldn't import the shared climb
database. That's fixed now — no more 100 MB Kilter-DB downloads
for every new user.
Also in 0.1.1:
• Progress bar stuck at 0% during initial board import — fixed
• Crash on older devices with large DBs — fixed
• Splash logo invisible in light mode — fixed
• Move count for boulders, frame count for routes
• Onboarding skips download if the DB is already there
• APK + release notes on Codeberg (no more Zapstore-only)
Step-by-step guide for Local Share in the reply 👇
Get the update / latest release:
• @npub10r8…t2p8 (recommended): https://zapstore.dev/apps/com.cruxcoach.android
• Codeberg APK + changelog: https://codeberg.org/CruxCoach/CruxCoach/releases
#climbing #bouldering #climbstr #bouldstr #crimpstr #kilterboard #foss #android

2026-04-14 20:13:57 UTC

Introducing CruxCoach — a free, open-source Kilter Board climbing app for Android.
https://npub1uadpshqpn5ysf82lev8zngkvn07szmkq7mvf9lyc7ml7qxq6fqxsmrqt2s.blossom.band/bb88307f9f4d1c695c90a346dca2f56ceaf6207fbd22fb69e2d850b9569d1132.png
🎨 Custom LED colors — visible to everyone at the board
📡 Share climbs with nearby users over Bluetooth — no internet needed
🔐 Your data stays on your device — encrypted, no cloud, no tracking
85,000+ climbs · filters · lists · heatmap · logbook import · stats
Get it on @npub10r8…t2p8 : https://zapstore.dev/apps/com.cruxcoach.android
Source: https://codeberg.org/CruxCoach/CruxCoach
#climbing #bouldering #climbstr #bouldstr #crimpstr #zapstore #introductions