Comparison

Della+ vs Rinnai Central

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

Head to head
About

Della+

Control smart home appliances remotely for optimal comfort and energy efficiency. Adjust settings, automate temperature based on location, and integrate with voice assistants for a seamless living experience.

Highlights
  • Remote appliance control
  • Smart feature integration
  • Energy efficiency
  • Voice assistant compatibility (Alexa, Google Assistant)
  • WiFi connectivity
  • GeoFence temperature adjustment
Features
Read full description

DELLA believes your home should always feel just right. Our appliances combine smart features, energy efficiency, and sleek designs to create a sustainable living environment. Compatible with Alexa and Google Assistant, the DELLA+ app offers complete control via your smartphone, with seamless WiFi and GeoFence functionality that adjusts temperature as you return home. With DELLA, you can dial in perfect comfort from anywhere and have your best home.

About

Rinnai Central

This app connects Rinnai tankless water heater owners to their devices for temperature control and scheduling. Professional installers can use it to register appliances, perform service, access documentation, and order parts.

Highlights
  • Adjust water temperature
  • Schedule hot water
  • Activate recirculation
  • Register appliances
  • Perform remote service
  • Access documentation
  • Order replacement parts
Features
Read full description

Rinnai Central helps professionals support customers and gives homeowners convenient control of compatible Rinnai water heating systems from anywhere. For Rinnai PROs and installers, Rinnai Central makes it easier to register products, set up compatible customer devices, access service tools, and stay connected to Rinnai resources. For Rinnai tankless water heater owners, Rinnai Central provides convenient access to temperature control, recirculation settings, scheduling, system status, and maintenance alerts when supported by the connected product. PROFESSIONALS Use Rinnai Central to: ∙ Set parameters and perform service on compatible Rinnai tankless water heaters and boilers. ∙ Register eligible Rinnai products after installation. ∙ Set up and configure compatible customer Wi-Fi modules. ∙ Access product documentation, troubleshooting tools, training, rebates, news, and service resources. ∙ Find the right Rinnai product for your customer's needs. ∙ Access the Rinnai parts webstore. ∙ Manage your professional account and company relationship. ∙ Participate in eligible Rinnai PRO Tech programs when available. HOMEOWNERS Use Rinnai Central to: ∙ Adjust compatible water heating system temperature settings. ∙ Activate recirculation when supported by the product. ∙ Create daily schedules so hot water is ready when needed. ∙ Set vacation mode to help save energy when hot water is not needed. ∙ View real-time system status and maintenance alerts. ∙ Find experienced Rinnai PROs and installers near you. COMPATIBLE PRODUCTS Rinnai Central supports select Rinnai residential and commercial tankless water heaters and compatible accessories. Some features require a supported Rinnai Wi-Fi module or compatible connected product. Product availability, supported features, and access permissions may vary by model. - BLE setup is not available on all Rinnai products. Some products may require the RWM200 Wi-Fi Module accessory, sold separately. - For safety and product support reasons, some device setup and service permissions may be restricted to Rinnai professionals. Read our Data Use and Privacy Policy, Terms, and other important information in the legal section of our App Store description or at the web addresses below. TERMS OF SERVICE https://www.rinnai.us/terms-of-use PRIVACY POLICY https://www.rinnai.us/privacy-policy

Screenshots

Della+4 screens
Rinnai Central4 screens

Verdict

The call

The clearest difference is rating: Della+ at 3.6 against Rinnai Central's 1.6. Della+ also leads on iOS requirement (13.0 vs 15.4.1). Rinnai Central's advantage is update cadence (monthly vs every 3 months). On price, review sentiment, ratings volume and 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Della+ holds the better App Store score, 3.6 against 1.6. Both are backed by a comparable volume of ratings — 435 and 398 respectively. Written reviews split almost evenly too, at 9% and 9% positive.

UpkeepUpdate frequency

Della+ ships an update every 3 months, Rinnai Central monthly. The most recent releases landed on October 30, 2026 and November 3, 2026 respectively.

Scorecard3 real differences · 7 level
Della+ versus Rinnai Central: the parameters behind the verdict, then further details
ParameterDella+Rinnai Central
PriceFreeFree
Rating3.6 (435 ratings) — better1.6 (398 ratings)
Positive reviews9.4% of reviews — better9.0% of reviews
Number of ratings435 — better398
Update frequencyEvery 3 monthsMonthly — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone, iPad, iPod
Requires iOS13.0 — better15.4.1
Further details — not scored
Size241 MB79 MB
Age rating12+4+
DeveloperAlign Inc. (CA)Rinnai America Corp

Customer experience

Della+

All ratings423 ratings
Positive63.4%
Neutral4.3%
Negative32.4%
Written reviews106 reviews
Positive9.4%
Neutral8.5%
Negative82.1%

Rinnai Central

All ratings341 ratings
Positive12.6%
Neutral3.5%
Negative83.9%
Written reviews223 reviews
Positive9.0%
Neutral4.5%
Negative86.5%

User reviews

Della+

From 435 App Store ratings

What we love

  • 🚀 Easy to use
  • 👍 Integrated seamlessly with product
  • 💡 Connects to other products

Room to improve

  • 🐛 App doesn't work properly
  • 🐛 Can't increase temperature
  • 🐛 Connectivity issues
  • 🐛 Removed features after update
  • 🐛 Confusing interface

Rinnai Central

From 398 App Store ratings

What we love

  • 🚀 Works great
  • 🚀 Much improved
  • 🚀 Fantastic
  • 🚀 Working perfectly now

Room to improve

  • 🐛 Doesn't work at all
  • 🐛 Bug in 4.3.0
  • 🐛 Awful. Just terrible
  • 🐛 Lousy App
  • 🐛 Rinnai does not care

Bugs and requests

Della+

Reported bugs

4 issues
  • App freezes or becomes unresponsive
  • Fails to connect to devices
  • Loses saved settings and configurations
  • Displays incorrect or inconsistent information

Requested features

6 requests
  • Add ability to increase temperature
  • Restore removed features
  • Improve app stability and reliability
  • Enhance user interface and controls
  • Add support for more device models
Show 1 more
  • Provide better customer support

Rinnai Central

Reported bugs

3 issues
  • Control failed is still happening in latest version
  • Login screen freezes
  • Incompatible with older devices

Requested features

3 requests
  • Add device through Bluetooth missing
  • Dark mode option
  • Advanced analytics dashboard

In-app purchases

None

Della+

No in-app purchases

None

Rinnai Central

No in-app purchases

Questions

Is Della+ free?
Della+ is free to download, with no in-app purchases.
Is Rinnai Central free?
Rinnai Central is free to download, with no in-app purchases.
Which has better reviews, Della+ or Rinnai Central?
Della+ is rated higher. Della+ averages 3.6 out of 5 from 435 ratings, while Rinnai Central averages 1.6 from 398 ratings.
Do Della+ or Rinnai Central have ads?
Neither Della+ nor Rinnai Central shows ads.
Which is updated more often, Della+ or Rinnai Central?
Della+ ships an update every 3 months, and Rinnai Central monthly. Most recently, Della+ was updated on October 30, 2026 and Rinnai Central on November 3, 2026.

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