Comparison

Sign Drops 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

Sign Drops

Manage and track sign placements for events, yard sales, or campaigns. Record detailed notes and precise locations for each sign, and oversee multiple events simultaneously for efficient organization and retrieval.

Highlights
  • Intuitive sign tracking system
  • Detailed notes and precise locations
  • Multi-event management
  • Seamless sign retrieval
  • Maximizes visibility and impact
Currently charting
Read full description

WELCOME TO SIGN DROPS - the must-have app for anyone managing sign placements, from bustling yard sales to impactful political campaigns. If your mission involves distributing signs to drum up visibility and engagement, Sign Drops is crafted just for you! KEY FEATURES: - SIGN TRACKING PERFECTION: Effortlessly monitor every sign's placement with our intuitive tracking system. Whether it's one sign or hundreds, Sign Drops ensures you're always in control. - DETAILED NOTES & LOCATIONS: For each sign placement, add comprehensive notes and record precise locations. This feature is a game-changer for planning your strategy and ensuring you can easily retrieve signs post-event. - **MULTI-EVENT MANAGEMENT:** Juggling multiple events? No problem! Sign Drops allows you to track several events simultaneously, keeping you organized and focused. WHY CHOOSE SIGN DROPS? In the dynamic world of event organizing and campaigning, Sign Drops serves as your personal assistant, ensuring that your sign management is seamless, efficient, and stress-free. By enabling precise tracking, detailed note-taking, and location marking, retrieving signs becomes a breeze, saving you time and effort. ELEVATE YOUR CAMPAIGNS & SALES: Sign Drops isn't just about placing and retrieving signs; it's about maximizing your visibility and impact. With the ability to oversee multiple events and their active statuses, you're equipped to make strategic decisions that amplify your message. Ready to streamline your sign management and take your campaigns to the next level? Download Sign Drops today and experience the ultimate in convenience and efficiency. Let's make every sign count with Sign Drops - Your strategic partner in visibility and engagement.

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
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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

Sign Drops4 screens
VPD Chart4 screens

Verdict

The call

The clearest difference is price: VPD Chart at Free against Sign Drops's $1.99. VPD Chart also leads on update cadence (every 3 weeks vs every 7 months) and ratings volume (30 vs 1). Sign Drops's advantage is rating (5.0 vs 4.5) and in-app purchases (none vs 2). On ads 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

VPD Chart is free to download; Sign Drops costs $1.99 up front. VPD Chart sells 2 in-app purchases, starting at $3.99 per month. Sign Drops asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Sign Drops holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: VPD Chart has 30 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Sign Drops ships an update every 7 months, VPD Chart every 3 weeks. The most recent releases landed on September 19, 2026 and September 22, 2026 respectively.

Scorecard9 real differences · 2 level
Sign Drops versus VPD Chart: the parameters behind the verdict, then further details
ParameterSign DropsVPD Chart
Price$1.99Free — better
Rating5.0 (1 ratings) — better4.5 (30 ratings)
Positive reviews—73.7% of reviews
Number of ratings130 — better
Update frequencyEvery 7 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
Best chart rank#198 — better—
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS17.415.1 — better
Further details — not scored
Size21 MB49 MB
Age rating4+4+
DeveloperJeremy BarrINNOVO DEV S.R.L.

Customer experience

Sign Drops

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

VPD Chart

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

In-app purchases

None

Sign Drops

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 Sign Drops free?
Sign Drops costs $1.99, with no in-app purchases.
Is VPD Chart free?
VPD Chart is free to download, with in-app purchases available.
Which has better reviews, Sign Drops or VPD Chart?
Sign Drops is rated higher. Sign Drops averages 5.0 out of 5 from 1 ratings, while VPD Chart averages 4.5 from 30 ratings.
Do Sign Drops or VPD Chart have ads?
Neither Sign Drops nor VPD Chart shows ads.
Which is updated more often, Sign Drops or VPD Chart?
Sign Drops ships an update every 7 months, and VPD Chart every 3 weeks. Most recently, Sign Drops was updated on September 19, 2026 and VPD Chart on September 22, 2026.

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