Show HN: MBCompass – Android Compass App
github.comHey HN,
I built MBCompass, a lightweight, privacy-friendly compass app for Android. It works fully offline, doesn’t ask for unnecessary permissions (no GPS, no internet), and is open source.
Most compass apps out there are bloated or ad-heavy. I wanted something clean, fast, and featurish. So I made this!
It’s only ~1.7 in size and uses a low-pass filter to smooth sensor readings.
I’d love feedback or thoughts – especially from others building simple, privacy-first apps!
Internet is useful for updating the declination "constants" for your location. Otherwise, the compass is not really very accurate in all locations.
https://www.rei.com/learn/expert-advice/compass-declination....
My next milestone is to implement magnetic declination correction using GPS. That way, the app can provide more accurate results by adjusting magnetic readings to true north while still respecting user privacy. Thanks for the great suggestion!
Would be great to have the option to input a major city and have it in a lookup table instead of requiring gps to be on and additional permissions.
This doesn't work like that, mate! OSM has a tile server limit policy because it operates on donations for the server. We need to adhere to this, so I do as much as I can to limit the tile server use. Once I have enough users. I will self-host it and add additional features. Thanks for asking.
Do you really need a DB lookup for declination? I'd imagine it can be worked out from lat/long and a single stored magnetic north location (although I suppose that might need updating).
Yeah, magnetic declination can be calculated using just lat/lon from GPS location.
I am curious what your experience with a free and ethical app in a walled garden will be.
I had a similar idea. About two years ago my kid was playing a simple mobile game with her friends a lot. There are many variations of the game theme but they are all ad infested privacy nightmares listlessly fiddled together.
I thought we could do better and make a good and ethical version - also as an educational project. The game turned out well, but we haven't published it yet. It is still planned, but I had to learn free apps apparently are an uphill battle in walled garden ecosystems.
If you think about it, it makes sense: Apple and Google don't like to get their 30% cut from nothing. I believe that is the deeper reason apps like ours are so rare.
> free apps apparently are an uphill battle in walled garden ecosystems.
How so? I manage well over 10 App Store Connect and around 7 Android Play Store accounts all with 1-3 apps in them, all free, no IAP, no cut for Apple. I've never felt like it was an uphill battle.
While the app review process is incredibly flawed, I haven't experienced anything that paid apps or apps using IAP run into as well. As in, free apps aren't "targeted" in any way I can see.
Appreciate your perspective — and I agree, technically, free apps can be published without issue. But from my experience (and others I've followed in the FOSS space), the “uphill battle” isn't about being blocked or targeted — it’s more about discovery, sustainability, and alignment with the platform’s incentives.
On stores like Google Play, the design favors apps with ad revenue, IAPs, or growth metrics — not minimal, ethical apps with no monetization. Free, privacy-respecting tools often get buried or flagged for things like lack of user engagement, sparse permissions, or not following monetization guidelines (like not using Google’s billing).
That’s why I released my app, MBCompass, on F-Droid first. It's where users expect simple, ethical apps — and where visibility isn't tied to commercial strategy.
So yeah, free apps aren't “targeted,” but the environment isn’t really designed to support or surface them either.
Ahh, yes. Getting customers or even showing up in search is a whole different ballgame.
Thankfully, I don’t have mess with any of that. All the apps I oversee are companion apps to another service. I’m not trying to attract people _on_ the AppStore to my app. People get the app because they use the service.
That makes a lot of sense — but apps like mine in the “Compass” category really struggle to stand out among countless bloated, ad-filled apps with hundreds of millions of downloads.
What's the incentive to "stand out" though if there is no monetization? It seems to me if there is no motive beyond just publishing an ethical X, then if users find it, they find it, and if they don't, they don't. And those looking for ethical apps (by your implied definition) will probably find it too; I've found a decent amount by filtering out apps with ads and IAP. Although TBF I use Aurora Store, and am unsure if the filter is available in the native Play Store app.
Totally agree — it's tough putting something ethical and free into platforms that are built around ads and in-app purchases. I released MBCompass on F-Droid first for that reason, and I’m still figuring out how to reach users who care about privacy and simplicity.
Please do. You can host on both fdroid and Google play / app store for free. F droid constantly needs high quality apps and passion projects are enjoyed by the community well.
I spent a lot of time doing free QA for F-droid apps exclusively and there are a lot of people who do that
Thanks! I don’t have a Play Store account yet due to budget, but this is on my to-do list.
You can start on f droid and maybe people can chip in to fund that
Yeah, that’s the plan! Honestly, building apps like this is tough — especially when aiming for unique features, keeping the app lightweight, and staying up-to-date with the latest tech stack. Support from the community really helps keep it going. :)
link me up when yours is online.
Thanks, I will do it.
@skeledrew Fair question! For me, the drive comes from passion and the joy of building something clean and useful. It’s less about standing out for fame, more about being found by the right people — folks who value FOSS, privacy, and ethical software. And yeah, alternative stores like Aurora or F-Droid make that discovery easier. :)
My favorite simple compass app is https://github.com/Kr0oked/Compass which is also on f-droid.
Pretty snappy, almost matches the refresh rate and latency of the iphone's compass app.
TFA looks way more sluggish, but I guess it is an effect of the smoothing.
Thanks for the comparison! Yeah, MBCompass applies smoothing intentionally to reduce jitter on noisy sensors — especially on low-end devices. That can make it look a bit less snappy, but I'm working on making it more responsive without sacrificing stability. Appreciate the feedback!
It would be really useful if it could show true north in addition to magnetic north. The location should give you declination.
Thanks! I’ve actually already answered this earlier in the thread — true north using declination based on location is my current milestone. I know how important it is for a modern compass app and am working on it
Can you make it a widget so it stays on the screen?
Thanks for the great idea! I’ve noted it down and will look into it for a future update
Try charging 99c for the widget...
I think instead of charging for app features, I’d prefer to add a donation page — if users like the app, they can support it. If not, no problem — it’ll always be free to use.
Why does this app need network permissions?
Good question! It needs network permission only to load the OpenStreetMap tiles for showing your location on the map. No data is collected or sent anywhere — privacy is a core focus. :)
Does Android not have a Compass app?
Yeah, all Android phones have compass apps or Google Maps features. But MBCompass is unique because it’s fully open source, privacy-friendly, and super lightweight — no ads or trackers, and works offline. Plus, it shows your location on an OpenStreetMap-based map, which most compass apps don’t have.
Thanks for asking! :)
Hmm I don't recall ever seeing one on early devices (been using Android since Cupcake), and there definitely isn't one on my current (OnePlus 12, Android 15). Always had to download from the Market/Store when needed.
AOSP doesn't even have a calculator anymore, I'm not sure it actually has a compass.
Exactly — AOSP dropped a lot of basics. That’s part of why I built MBCompass. :)
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Trail Sense is awesome — love the survival tools, and sun/moon data! MBCompass is more focused: great for quick direction checks, offline use, and showing your location on OSM with zero clutter.
I've been using Organic Maps though there is some kind of more community-oriented fork of it now, that I should check into.
It would be cool to add a solar compass feature to MPCompass. I've been wanting to suggest that to the Trail Sense author too.
https://en.wikipedia.org/wiki/Burt%27s_solar_compass
That’s a cool idea — I hadn’t heard of Burt’s solar compass before! Would be fun to explore as an optional mode in MBCompass. Thanks for the link — I’ll definitely read more into it.