Comparison

OpenSprinkler vs VPD Chart

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

OpenSprinkler

Control your OpenSprinkler irrigation system remotely. Monitor device status, modify watering schedules, and launch programs instantly. Features manual testing, multi-device support, and weather integration.

Highlights
  • Device status monitoring
  • Program modification
  • Instant program launch
  • Manual testing mode
  • Multi-device support
  • Weather and forecast integration
  • Log data visualization
Features
Read full description

The application allows you to automatically detect and control your OpenSprinkler irrigation system(s). OpenSprinkler is an open-source Internet web-based sprinkler timer / controller built upon the Arduino platform. Features of the app include: * Easy to understand device status * Quick program modification * Launch ad-hoc or defined programs instantly * Manual mode for convenient testing * Multi-device support * View visual representation of upcoming scheduled programs * View graphical and tabulated representation of log data * View current weather and forecast status for the device location * Change and disable rain delay * Multiple supported languages (Afrikaans, Amharic, Chinese, Czech, Dutch, French, German, Hebrew, Hungarian, Italian, Mongolian, Norwegian, Polish, Portuguese, Slovak, Slovenian, Spanish and more) This application requires you to own an OpenSprinkler that is properly connected to your network. For more information please visit https://opensprinkler.com. You can control your device from outside the local network with proper port forwarding and use of the WAN IP within the application or by using a VPN. For further assistance please visit the forums: https://forums.opensprinkler.com This is open source software: source code for this application can be found at https://github.com/OpenSprinkler/OpenSprinkler-App

About

VPD Chart

This app calculates Vapor Pressure Deficit (VPD) using air temperature, relative humidity, and canopy temperature. It offers real-time charting, sensor integration, and educational tools to understand plant growth environments. Organize data by zones and visualize dew point areas.

Highlights
  • VPD calculation
  • Interactive VPD chart
  • Sensor integration
  • Zone organization
  • Dew point visualization
  • Grow Timeline
Features
Read full description

The app calculates VPD using air temperature, relative humidity, and canopy temperature. View real-time VPD values on an interactive chart. Connect sensors for automated readings or manually input data via intuitive sliders and text inputs. Key features: • Interactive VPD chart with manual input • Default crop types • Organize charts by assigning them to different zones • Display spots that share the same VPD value • Zoom in and out of the VPD chart with a two-finger pinch and drag to pan around • VPD Target - long-press the chart to set a target VPD value • Dew point area visualization • Grow Timeline • Sync sensor historical data by importing it from sensor's app, via cloud APIs, or bluetooth • Explore sensor history by panning and zooming Supported bluetooth devices: • AC Infinity Cloudcom B2, A2, B1 • SensorPush: HT1, HT.w, HT.xw • Govee: H5051, H5072, H5074, H5075, H5100, H5101, H5102, H5103, H5104, H5105, H5174, H5177, H5179 • SwitchBot: Meter, Plus, Indoor Outdoor • Ruuvi: RuuviTag and RuuviTag Pro • Inkbird: IBS-TH1, IBS-TH1 Plus, IBS-TH2, IBS-TH2 Plus • ThermoPro: TP351, TP357, TP358, TP359 • VIVOSUN AeroLab THB1S • Shelly BLU H&T • Xiaomi Mijia 2 (LYWSD03MMC) (original and pvvx firmware) Supported devices with API connectivity: • Govee • Pulse • UbiBot • Ecowitt • Tuya • SensorPush Educational benefits: • Interactive Learning: Explore the dynamics of VPD based on changes in temperature and relative humidity by manipulating input sliders and animating the chart • Canopy - Air Temperature Link: Easily visualize and set values by linking canopy temperature to air temperature • Chart Bands Control: Toggle chart bands on/off (dew, under transpiration, prop, veg, flower, over transpiration) for a comprehensive understanding Included: 1 chart with manual input and grow timeline, device data sync & explore, default crops VPD Chart Plus subscription unlocks: • Unlimited charts • Automated VPD calculation by using sensors as the input data source • Background monitoring and Alerts (temperature, RH, VPD) • VPD history timeline, available on sensor-driven VPD charts • Custom crops Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

OpenSprinkler3 screens
VPD Chart4 screens

Verdict

The call

The clearest difference is rating: VPD Chart at 4.5 against OpenSprinkler's 3.9. VPD Chart also leads on update cadence (every 3 weeks vs every 2 months) and review sentiment (74% vs 65%). OpenSprinkler's advantage is in-app purchases (none vs 2). On price, ratings volume, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. VPD Chart sells 2 in-app purchases, starting at $3.99 per month. OpenSprinkler asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

VPD Chart holds the better App Store score, 4.5 against 3.9. Both are backed by a comparable volume of ratings — 29 and 30 respectively. Written reviews point the same way: 65% of OpenSprinkler's written reviews are positive against 74% of VPD Chart's.

UpkeepUpdate frequency

OpenSprinkler ships an update every 2 months, VPD Chart every 3 weeks. The most recent releases landed on September 24, 2026 and October 9, 2026 respectively.

Scorecard5 real differences · 5 level
OpenSprinkler versus VPD Chart: the parameters behind the verdict, then further details
ParameterOpenSprinklerVPD Chart
PriceFreeFree
Rating3.9 (29 ratings)4.5 (30 ratings) — better
Positive reviews64.8% of reviews73.7% of reviews — better
Number of ratings2930 — better
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.0 — better15.1
Further details — not scored
Size6 MB49 MB
Age rating4+4+
DeveloperOpenThingsINNOVO DEV S.R.L.

Customer experience

OpenSprinkler

All ratings29 ratings
Positive72.4%
Neutral10.3%
Negative17.2%
Written reviews54 reviews
Positive64.8%
Neutral13.0%
Negative22.2%

VPD Chart

All ratings30 ratings
Positive86.7%
Neutral3.3%
Negative10.0%
Written reviews19 reviews
Positive73.7%
Neutral0.0%
Negative26.3%

In-app purchases

None

OpenSprinkler

No in-app purchases

2 purchases

VPD Chart

Subscriptions2
  • VPD Chart Plus (monthly)3 Days trial$3.991 Month
  • VPD Chart Plus (annual)3 Days trial$29.991 Year

Questions

Is OpenSprinkler free?
OpenSprinkler is free to download, with no in-app purchases.
Is VPD Chart free?
VPD Chart is free to download, with in-app purchases available.
Which has better reviews, OpenSprinkler or VPD Chart?
VPD Chart is rated higher. OpenSprinkler averages 3.9 out of 5 from 29 ratings, while VPD Chart averages 4.5 from 30 ratings.
Do OpenSprinkler or VPD Chart have ads?
Neither OpenSprinkler nor VPD Chart shows ads.
Which is updated more often, OpenSprinkler or VPD Chart?
OpenSprinkler ships an update every 2 months, and VPD Chart every 3 weeks. Most recently, OpenSprinkler was updated on September 24, 2026 and VPD Chart on October 9, 2026.

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