Product Release Notes

Last updated: 03/06/2023

iOS app (v1.2.1) (March 2023) available at the App Store

Android app (v1.1.0) (March 2023) available through Google Play

Predictive Thermometer + Display

This is to let you know what’s working well, what’s not (and what we’re doing about it), and what’s up next for the Predictive Thermometer + Display.

Much as we would love to say the Predictive Thermometer Set is perfect, exactly how we want it, straight-out-of-the-box, it isn’t. There will be growing pains for the first couple of months.

On the other hand, this already is the most advanced cooking thermometer ever built (not exaggerating), and we’re not even done yet. Stick with us, you’ll see. 

If you run into a snag, please check the owner's FAQ (below). If you don’t find the answer you need, email us.


The most important functions of the Predictive Thermometer are software-controlled — there's a remarkable amount of computing power stuffed in there. It makes all kinds of important calculations, including predictions.

The more cooking data we feed into our algorithm ( Predictive Engine), the better it gets. Our new Predictive Engine is better than the one from a month ago (and the next one will be even better). 

It also means we can add new features like advanced cooking predictions, without having to rebuild anything. New firmware is like getting a free upgrade to your hardware.

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How to update firmware on the Predictive Thermometer + Display

You'll need the "Combustion Inc." app to apply firmware updates.

iOS app download

Android app (updater only) download

Please update your tools one at a time (e.g. do the Predictive Thermometer first, then the Display).

Step-by-step (iOS):

1. Search "combustion inc" on the App Store.

2. Click "get"

3. Click "install" (wait for it to finish)

4. Click "open"

5. Remove your fully charged thermometer from the charger. Place your mobile device very near your thermometer (within a few inches). 

6. Click the fire icon (Combustion Inc logo)

7. Click "update" in the top area (thermometer)

8. Wait about a minute until it says "up to date"

9. Put your thermometer back in the charger and move it away from your mobile device. 

10. Turn on the Display (press start), and put it near your mobile device.

11. Repeat steps 6-8 for the display 

12. Nice work! Your firmware is now up to date

13. Recharge the thermometer before use

14. Press “cancel” to close out of the update screen and return to the main menu 

(Note: if you have more than one thermometer, repeat steps 5-8 one at a time for each.)

Step-by-step (Android):

1. Search "combustion inc" on Google Play - select the "Combustion Updater" app
2. Click “install”
3. Click "open"
4. Turn on device (one at a time) (start with the thermometer - remove it from the charger to turn it on)
5. Confirm Bluetooth permissions
6. Click “Search”
7. Select the tool (thermometer)
8. Click “Start”
9. Wait for update to complete
10. Put the thermometer back in the charger
11. Press “start” on the Display
12. Repeat steps 6-9
13. Your tools are now updated! (They should show firmware v1.1.0)
14. If you have another thermometer, turn off your other tools (hold start on the Display), remove the 2nd thermometer from its charger, then repeat steps 6-9
15. Close the updater app

If the update does not complete, close the app and re-open it. Check the firmware status - if it does not show v1.1.0, try again.

Firmware Release Notes (v1.1.0)


• Better battery life

• Faster instant-read time

•Several nasty bug fixes (see known firmware issues below)

• Fixes an issue which caused increased power consumption during low-and-slow cooking

(Dec 23, 2022)

Known Firmware Issues (v1.0.2)

Until you update your firmware, you might encounter some of these misbehaviors. They’re not necessarily bugs, just stuff we aren’t completely happy with and have since fixed.

Here are some issues users have encountered (confirmed by our team). To submit a bug report, email us.

• Occasional erratic behavior of “time-to-cook” on the display - this can happen when the heat input changes greatly (for instance in a reverse sear) - the prediction will recalculate but because of how this firmware version  set up, it will look like the time is running off too rapidly or sometimes it will add time back to the prediction. If you see this, it probably means you’re very close to done, so pay attention to the temp and listen for the beep.

• Low battery life on high-temp long-duration cooks - after the thermometer reaches the cook to temp, it will switch back into “instant read mode.” Unfortunately that means it consumes much more power (because it’s transmitting more frequently). If you’re cooking for more than 6 hours, you may see this problem. D’oh! If the thermometer battery dies mid-cook, remove it, clean it, charge it back up (5 min should be plenty for most cooks) and put it back in to resume monitoring. Not ideal. 

• Oscillating instant reading temperatures. When you take an instant-read, the filter that speeds up the temperature display is slightly unstable because of some last minute changes we made to the hardware. You’ll tend to see the temperature overshoot and then oscillate as it slowly settles to correct value over 15 seconds or more. It’s very annoying and something we’re fixing in the next firmware update.

Planned features

Among other things, the team at Combustion is currently working on the following for early 2023.

  • Faster/more stable instant-reads. 
  • More robust Bluetooth connectivity and better handling of temporary disconnects
  • Carryover cooking (resting) predictions
  • Improved battery life when in instant read mode


We pushed the limits of what is possible, and some of those limits pushed back. Real-world testing revealed some limitations in the physical product - stuff we didn’t discover until we had more people cooking with different appliances in a wider variety of different ways.

Some of these issues can be fixed, but some are bumping up against the laws of physics and thermodynamics and we just need to work around them.

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Sous vide, vacuum-sealing, and submersibility

Ah, meat juices. The greatest ally and occasional nemesis of the Predictive Thermometer. 

Beta testers have had some troubles with sous-vide so we’re currently recommending against doing that (for now). Chris is leading an investigation into whether using a vacuum is pulling meat-juice through the main seal. We vacuum-test every unit in QA, so it might only be a problem with older units. Stay tuned. 

Until you hear differently, abstain from using your thermometer inside the sous vide bag. 

Standby-mode thermometer battery life

We discovered a power leak during standby mode, which cuts standby time down to two weeks (from four). It’s a small but significant leak. Charging up the thermometer after it’s been in the drawer a couple weeks is probably a good rule of thumb.

Personally, I got in the habit of topping mine off with a 5 minute zap on any day I’m going to use it. Not ideal, but you probably won’t ever notice if you’re using it regularly.

Signal strength and heavy metal grills

Rec-tec defeated us. Sort of. (If you didn’t know, they’re a brand that builds grills that weigh about the same as a battleship.)  

The thicker the metal, the more it blocks radio. Even a strong transmitter (like the one inside the Predictive Thermometer) inside a bomb-proof 10-gauge plate-metal enclosure is going to have signal issues. 

A Predictive Thermometer inside one of these monster grills can get a weakened signal through – though reception depends on the proximity and orientation of the display.

We plan to release a set of universal rabbit ears that will mount to any smoker or grill (just kidding --- unless??).

For now, we sussed out a different way to make the most of mostly-blocked signals.

Thankfully, the Predictive Thermometer is doing the heavy calculations, so an intermittent connection is enough to keep your display up-to-date.

And even though this ties your display closely to the grill, you'll be able to use it as a range-booster and track your progress on the app from much farther away. The repeater gets you about 200 added feet of signal range (+61m). So unless your bomb-proof grill is also in a bunker, you should be freed up a bit.

More about RF and Bluetooth on the main FAQ ("All about wireless").


Even if you don’t plan to cook using an app, you’ll need it in order to update your firmware (it’s bone-simple to do so, we promise).

The apps also unlock an important feature of the Combustion Display: the Range Extender. When using the display + app, total signal strength is best-in-class: 330ft (100m)!

You don’t need an account to use any of our products. We intentionally kept the app very streamlined. It won’t push ads or recipes or other content at you.

The app shows you temperatures in and around your food, and let you know when your food will be done. No fluff.

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iOS Combustion Inc. app v1.2 - features (Mar)

iOS v1.2.1

(March 4, 2023)

Release notes:

  • Thermometer naming! Give your thermometer an easy-to-remember name. Especially useful when you have more than one Predictive Thermometer.
  • CSV data export. When the app is in range of the thermometer (not using the Display as a booster), you can export the FULL COOKING DATA. We use that data to improve predictions and stuff, but you can do whatever you want with it inside Excel or Sheets (or your spreadsheet of choice). Data export paves the way for the next major feature: graphing!
  • Bug fixes and reliability improvements. 

(Feb 10, 2023)

  • Disconnect alerts are now less aggressive (sorry about that)
  • Reconnect notification removed
  • Disconnect alert will now only fire after 60 seconds and only when a cook is active ("cooking to" is set)
  • Reconnecting will now clear any disconnect alert

(Feb 06, 2023)

  • Advanced alerts now play when the app is in the background
  • Ready, 5-min Warning, Overheat, Disconnect, and Low Battery notifications
  • Persistent "ready" alarm
  • New overheat warnings
  • Reconfigured, less-sensitive overheat "red alert"
  • Stabilized ready-in countdowns
  • Bug fixes and reliability improvements

(Dec 23, 2022)

•Update firmware with minimal effort

•Set target (cooking to) temps

•View ambient, surface, and core temps

•Shows predictions

•Wander farther from the cooking area (see below)

When using the app, the display (timer) acts as a repeater – you can control and monitor your cook from another room, or across a small city park, or from a low-flying hot air balloon if necessary.

Android Combustion Inc. app v1.1 - features (Mar)

Android v1.1.0

Release notes:

  • Thermometer naming! Give your thermometer an easy-to-remember name. Especially useful when you have more than one Predictive Thermometer.
  • CSV data export. When the app is in range of the thermometer (not using the Display as a booster), you can export the FULL COOKING DATA. We use that data to improve predictions and stuff, but you can do whatever you want with it inside Excel or Sheets (or your spreadsheet of choice). Data export paves the way for the next major feature: graphing! 
  • Bug fixes. Everybody loves bug fixes.

Android v1.01

The Predictive Thermometer companion app lets you see the temperatures (core, surface, ambient) and predictions from your Predictive Thermometer, as well as set target temps, even from another room.

As long as your Combustion Display is within range, your app will function as a receiver and secondary display, extending the functional signal range - up to 300ft (90m). This is fabulous for those of us who live in old houses or decommissioned missile silos. 

Another practical use is when you’re cooking inside some radio-resistant metal enclosure like a heavy-walled grill or smoker. No problem! Place the Display near the cook to relay the signal and keep tabs with the app from a goodly distance. 

App Features: 

  • Use with Predictive Thermometer and/or Combustion Display (timer)
  • Use with Combustion Display to boost signal up to 300ft (90m)
  • Set target “cook to” temperatures and view “ready in” cook-time predictions
  • Tells you when your food is ready
  • See key temps: including core, surface, ambient temperature
  • Update firmware: better performance and new features for the Predictive Thermometer and Display
  • No accounts or sign-ins required

App-related questions

Q: When will the app be available?

A: Now!

Q: Where?

A: In the App Store (iOS) and Google Play (Android). Links are in the footer.

Q: What’s it called?

A: The app name is “Combustion Inc.”

Q: Does it work on tablets as well?

A: Yes, indeed.

Q: I thought I didn't need a phone?

A: You don't need one to cook, that's up to you. But you will need one to upgrade firmware occasionally. Maybe borrow one from your kids? Or a neighbor kid?

Q: What took Android so long?

A: We're a small team; the same developers building the Android app are also responsible for the firmware onboard your Predictive Thermometer. That wound up delaying the app longer that we would have liked. The iOS app team had a pretty big head start, but we’re catching up.

Planned features

Graphing: this is very cool and kind of hypnotic, trust me

Data exports: track your cooking results (released! March 2023)

High/low temp alarms

(alerts added to iOS in Feb 2023)

Multiple temperature alerts: nice for multi-step cooks like reverse sear

Signal strength + management

What's cookin' where ID (working title): label a cook-in-progress with a photo

Didn’t find the info you needed? Email us.

You may find answers on the main FAQ.

If you have other questions about cooking with the Predictive Thermometer, your best bet is to ask on our official subreddit. (Chris watches this and often responds personally.)

Please write us if you have a problem or would like to report an issue. (

Your feedback is super-important, it’s a big part of how we find ways to improve the product. Thanks for taking the time, we really appreciate it.

Happy Cooking!