Comparison

S7 Link vs Blue Switch

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

Head to head
About

S7 Link

Features
Read full description

A NEW APP, THE FUNCTIONS YOU KNOW • All the functions and tabs of previous versions are kept: pushbutton panel, manual commands, variables, alarms, point tables, PLC links, CPU status, date and time, backup and sharing • Updating keeps your connections, tables, options and purchases; backups made with iS7 can be restored SUPPORTED PLCS CPUs of the S7-300, S7-400, S7-1200 and S7-1500 families and LOGO!, reachable on the network through ISO on TCP (RFC 1006). S7-1200 and S7-1500 need PUT/GET access enabled and DBs without optimized access. IN-APP PURCHASE Alarm management on real PLCs is available as an in-app purchase. Whoever has already bought it keeps it. SAFETY S7 Link can write to PLCs and act on machinery in operation. Use it with care and at your own risk, and do not rely on it for safety functions. In the background, iOS decides when alarms are checked, and it can be hours apart. Requires iOS 26 or later. Siemens, SIMATIC and S7 are trademarks of Siemens AG. S7 Link is an independent product, not affiliated with or endorsed by Siemens.

About

Blue Switch

Control 2, 4, or 8 channel Bluetooth BLE relay modules from your iPhone or iPad. Assign custom names to modules and individual relays for easy identification and management. Enhance security by changing the default password.

Highlights
  • Control 2, 4, or 8 channel relay modules
  • Bluetooth BLE connectivity
  • Assign custom module aliases
  • Assign custom relay aliases
  • Change default password for security
  • Connect to multiple modules
Features
Read full description

This app allows you to control a 2, 4 or 8 Channel Relay Module Bluetooth BLE with your iPhone or iPad. To use this app, you need one of these three modules: "2 Channel Relay Module Bluetooth BLE" "4 Channel Relay Module Bluetooth BLE" "8 Channel Relay Module Bluetooth BLE" These modules can be ordered at many online shops. Please use a search engine to find a shop. This app can be connected with any number of modules. By entering an alias, the modules are marked clearly and can easily be assigned to a use area. Name the modules for example "Relay 1", "Relay 2", "Electronic lab project" or "Ambient Light". An alias can also be entered for each relay. The default password for these modules is usually "12345678". For more security, the app also allows you to change the password. The password must be eight digits long.

Screenshots

S7 Link4 screens
Blue Switch4 screens

Verdict

The call

The clearest difference is price: Blue Switch at Free against S7 Link's $14.99. Blue Switch also leads on iOS requirement (18.0 vs 26.0). S7 Link's advantage is ads (none vs shown). On update cadence, in-app purchases 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

Blue Switch is free to download; S7 Link costs $14.99 up front. S7 Link sells 3 one-off in-app purchases and Blue Switch sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

S7 Link ships an update every 4 months, Blue Switch every 3 months. The most recent releases landed on November 10, 2026 and November 6, 2026 respectively.

Scorecard3 real differences · 7 level
S7 Link versus Blue Switch: the parameters behind the verdict, then further details
ParameterS7 LinkBlue Switch
Price$14.99Free — better
Rating—3.8 (43 ratings) — better
Positive reviews—16.7% of reviews
Number of ratings—43 — better
Update frequencyEvery 4 monthsEvery 3 months — better
AdsNo — betterYes
In-app purchasesYesYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS26.018.0 — better
Further details — not scored
Size10 MB39 MB
Age rating4+4+
DeveloperCarlo TrottiVitalij Schaefer

In-app purchases

3 purchases

S7 Link

One-time3
  • Alarms$2.99
  • Charts$2.99
  • OPC Client$4.99
1 purchases

Blue Switch

One-time1
  • Remove Ads$17.99

Questions

Is S7 Link free?
S7 Link costs $14.99, and also offers in-app purchases.
Is Blue Switch free?
Blue Switch is free to download, with in-app purchases available.
Do S7 Link or Blue Switch have ads?
Blue Switch shows ads; S7 Link does not.
Which is updated more often, S7 Link or Blue Switch?
S7 Link ships an update every 4 months, and Blue Switch every 3 months. Most recently, S7 Link was updated on November 10, 2026 and Blue Switch on November 6, 2026.

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