Comparison

iSolergo vs Erebus Solar

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

Head to head
About

iSolergo

Features
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iSolergo lets you make the preliminary design of a photovoltaic system in a few minutes, with the energy analysis, the configuration of photovoltaic modules and inverters and evaluation of plant profitability. In preliminary inspection, the App uses the resources of the device to automatically determine location, orientation and inclination of the modules, in order to obtain a complete energy evaluation of the site, using the global database climate. So, you can proceed by selecting PV modules and their better coupling with the inverter you want. The application verifies all the conditions of consistency (voltage, current and power) between the inverter and string combinations proposed and used. Solergo can handle systems with inverter with more trackers connected to strings with different exposures. The software contains an extensive and multi-brand modules and inverters database, with all the technical characteristics necessary for the calculation of the production system, considering the losses due to thermal drift of the modules, mismatching, losses in DC and efficiency of the inverter. In few steps, choosing the installation situation, the method of connection and tariff iSolergo calculates the resulting revenues. Adding the typical costs for installation and management, with the overall economic analysis, you can evaluate the profitability of the system and the cash flows resulting. All the calculations are shown on charts and tables easy to understand, to provide the potential customer all the information clearly and complete. All project data are stored on a file standard Solergo (software for the complete design of photovoltaic systems), and can be sent directly or via e-mail to your office computer.

About

Erebus Solar

This app helps solar professionals measure on-site shade using their phone's sensors. It generates horizon files compatible with leading PV design software, aiding in accurate solar production estimates.

Highlights
  • AR sun path visualization
  • Automatic sky capture
  • Sky Editor for obstruction tracing
  • Annual solar access analysis
  • PDF shade report export
  • Horizon file generation for design tools
  • Project organization by site
Features
Read full description

Measure shade on site with the hardware already in your pocket. Erebus Solar was designed by an electrical engineer and an architect with years of experience designing solar systems around the world. We were fed up with the horizon-finding hardware the industry still relies on: dedicated devices that haven't been meaningfully updated in decades, are slow to use and slow to find a GPS fix, and analog tools that need paper, a pencil and a latitude template that may not exist for your site. Erebus Solar is our answer. Your iPhone already has the camera, compass and sensors the job needs. WHY HORIZON FILES MATTER Far-field shading from trees, terrain and neighbouring buildings is one of the largest sources of error in a PV production estimate. A measured horizon profile, captured on site, lets your design software model that shading instead of guessing. Erebus Solar produces horizon files that leading PV design tools such as HelioScope and PVsyst read directly, and PV*SOL accepts the same convention. CAPTURE • AR sun path: today's arc, the solstice and equinox arcs and the live sun drawn over the real sky • Tap the real sun to calibrate the compass to true north • Automatic sky capture: sweep the envelope band and frames capture themselves, no buttons • Sky Editor: review the stitched sky and trace obstructions by hand, so the report reflects what you saw ANALYSE • Annual solar access and TSRF for each array area • Month-by-month charts and the sun-path chart with your obstructions • Aerial view with each area's boundary and the solar envelope over satellite imagery EXPORT • PDF shade report with your company name and logo • Horizon files for HelioScope, PVsyst and PV*SOL, generated from the same capture • Share straight from the phone ORGANISE • One project per site, located by address or GPS, with status from Created to Completed • Areas for each roof face or ground section • Everything stored on your iPhone: no account, no upload Erebus Solar's outputs are a design aid for qualified professionals. Results depend on the phone's sensors, compass calibration and sky conditions; check them against your own observations and your design tool's simulation before relying on them. Privacy Policy: https://erebussolar.app/privacy Terms of Use: https://erebussolar.app/terms

Screenshots

iSolergo4 screens
Erebus Solar4 screens

Verdict

The call

The clearest difference is update cadence: Erebus Solar at every 2 weeks against iSolergo's every 9 months. iSolergo's advantage is device support (3 vs 1) and iOS requirement (11.0 vs 17.0). On price, ads and in-app purchases 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.

UpkeepUpdate frequency

iSolergo ships an update every 9 months, Erebus Solar every 2 weeks. The most recent releases landed on September 23, 2026 and October 14, 2026 respectively.

Scorecard3 real differences · 7 level
iSolergo versus Erebus Solar: the parameters behind the verdict, then further details
ParameteriSolergoErebus Solar
PriceFreeFree
Rating—3.7 (3 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—3 — better
Update frequencyEvery 9 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS11.0 — better17.0
Further details — not scored
Size63 MB19 MB
Age rating4+4+
DeveloperElectro Graphics SrlTodd Evans

In-app purchases

None

iSolergo

No in-app purchases

None

Erebus Solar

No in-app purchases

Questions

Is iSolergo free?
iSolergo is free to download, with no in-app purchases.
Is Erebus Solar free?
Erebus Solar is free to download, with no in-app purchases.
Do iSolergo or Erebus Solar have ads?
Neither iSolergo nor Erebus Solar shows ads.
Which is updated more often, iSolergo or Erebus Solar?
iSolergo ships an update every 9 months, and Erebus Solar every 2 weeks. Most recently, iSolergo was updated on September 23, 2026 and Erebus Solar on October 14, 2026.

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