iSpindle Plotter

6 Downloads 11 Views v0.5 16.27 MB 4.1+

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(16.27 MB)

Editor's Overview

iSpindle Plotter is a science & education application developed by Ian Williams, packaged as a single Android APK of version 0.5 weighing in at 16.27 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

Install Checklist

Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
File size is a light 16.27 MB, so it installs quickly even on modest connections.
This build is signed by "Ian Williams" — always verify the developer name matches what's listed on the app's official store page before installing an update.
After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

About this app

iSpindle Plotter is a self-hosted companion app for the iSpindel — an open-hardware floating hydrometer used by home brewers to track specific gravity through a fermentation. The app runs a small HTTP server on your phone that the iSpindel posts its readings to over your local Wi-Fi network, then stores, charts, and analyses those readings without ever sending your data to a third-party cloud service.

Pairing and configuration:

* Auto-pair flow that joins the iSpindel's configuration access point, sets the phone as the HTTP target (Generic HTTP / selAPI=3), reads the device's existing cubic calibration polynomial off the firmware, and reconnects to your home network — without losing pre-existing fields like the calibration on subsequent saves.
* mDNS-style hostname discovery so the iSpindel can find your phone again after either device's IP changes.
* Pushes the app's own calibration polynomial back to the iSpindel when you re-calibrate.

Calibration:

* Fit cubic / quadratic / linear polynomials from your own sucrose-dilution measurements.
* Imports the iSpindel's pre-installed factory calibration on first pairing.
* Setup guide with a sucrose-step-dilution recipe for 1.000–1.080 SG.

Plotting and analysis:

* Tilt angle, temperature, specific gravity, and battery voltage charts with a 24h / 7d / 30d / All time-window switcher.
* Potential-alcohol secondary axis on the SG chart.
* Robust phase classifier (Lag / Active / Slowing / Conditioning / Stuck / Cold crash) using a modified-Gompertz Levenberg-Marquardt fit (Zwietering et al. 1990), with fallback to an attenuation-prior when the data is too early to constrain the asymptote.
* Predicted final gravity overlaid on the chart with a tapering uncertainty band derived from short-time noise estimation and the calibration polynomial's residual.
* Battery runway estimate: linear discharge fit projecting time-to-cutoff at the current sample rate.
* Trim-before-date-and-time to drop pre-fermentation noise; CSV export via the system file picker.

Privacy:

* No analytics, no telemetry, no third-party network connections.
* Data is held only on your phone and only sent to your iSpindel's local IP for configuration writes.
* The app's HTTP server listens on the phone's local network address only.

Hardware: built and tested with an MTB iSpindel PCB 4.0; should work with any iSpindel firmware that supports the Generic HTTP target.

Details

Version	v0.5
Size	16.27 MB
Developer	Ian Williams
Category	Science & Education
Package	com.ispindle.plotter
Android	4.1+
Last Updated	Oct 29, 2026
Downloads	6

Frequently Asked Questions

Is iSpindle Plotter free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does iSpindle Plotter require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is iSpindle Plotter safe to install?
We link to the exact APK published by Ian Williams. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update iSpindle Plotter?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

How to Download & Install iSpindle Plotter

Tap the Download APK button above and save the file to your device.
Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
Open the downloaded com.ispindle.plotter.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «iSpindle Plotter» by Ian Williams and grant only the permissions it actually needs.
Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.