Comparison

SIMSY vs Walnut

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

Head to head
About

SIMSY

Features
Read full description

The SIMSY app is your gateway to a new mobile experience. SIMSY provides a mobile data service with a difference. Use our app to download our eSIM, order a physical SIM, top up your account and manage your mobile services. With our app you can get your MCP key, which allows you to integrate the SIMSY mobile solution directly into your favourite AI tool whether that's chat GPT, Claude, a perplexity or anything else you might want to use. • Use your MCP key to access the SIMSY MCP Server. • SIMSY allows you to integrate connectivity with a suite of AI tools including Lovable, Windsurf, Databutton, Cursor, RooCode and Replit. • Head to s-imsy.com to look at the available base applications and to see how you can use SIMSY to integrate with your other connected solutions. The SIMSY app enables quick, easy and free remote access into any of your devices, whether it’s Raspberry PI, home automation system, video cameras, Nvidia Jetson devices, home networks or anything else you can think of. You can also take your SIMSY SIM roaming, travel round the world with low cost data and only pay for the data you need to use. Your credit will not expire so you don't need to continually buy bundles.

About

Walnut

This app allows developers to test WKWebView and SFSafariViewController configurations in real-time. It offers built-in DevTools for console, network, storage, and performance analysis, along with JavaScript injection and accessibility auditing.

Highlights
  • Real-time WKWebView configuration testing
  • Built-in DevTools (Console, Network, Storage)
  • JavaScript injection and execution
  • SFSafariViewController testing with content blockers
  • Accessibility auditing (axe-core)
  • Responsive viewport and device emulation
  • Bookmark management
Features
Read full description

The ultimate developer tool for testing WKWebView and SFSafariViewController configurations in real-time. KEY FEATURES WKWebView Testing • Real-time configuration testing with 20+ options • Built-in DevTools: Console, Network, Storage, Performance, Sources, Accessibility • JavaScript injection and snippet execution • Custom User-Agent emulation • Viewport and device emulation SFSafariViewController Testing • Native Safari experience with content blockers • Reader mode and responsive size control • Customizable bar colors and dismiss button styles Developer Tools • Console: Capture console.log with %c CSS styling support • Network: Monitor fetch/XHR requests with timing data • Storage: View/edit localStorage, sessionStorage, cookies • Performance: Web Vitals (LCP, FID, CLS) and Navigation Timing • Sources: DOM tree inspection, stylesheets, scripts • Accessibility: axe-core based accessibility auditing Additional Features • Bookmark management for quick URL access • Responsive viewport resizing (iPhone, iPad, Desktop presets) • Screenshot capture • API capability detection • Dark mode support Perfect for iOS developers who need to test web content rendering, debug JavaScript, analyze network requests, and ensure accessibility compliance.

Screenshots

SIMSY4 screens
Walnut4 screens

Verdict

The call

The clearest difference is in-app purchases: SIMSY at none against Walnut's 1. SIMSY also leads on ads (none vs shown) and iOS requirement (16.0 vs 18.4). Walnut's advantage is update cadence (every 4 days vs monthly). On price 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. Walnut sells 1 one-off in-app purchase. SIMSY asks for nothing beyond the download.

UpkeepUpdate frequency

SIMSY ships an update monthly, Walnut every 4 days. The most recent releases landed on September 29, 2026 and October 9, 2026 respectively.

Scorecard4 real differences · 6 level
SIMSY versus Walnut: the parameters behind the verdict, then further details
ParameterSIMSYWalnut
PriceFreeFree
Rating—5.0 (1 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—1 — better
Update frequencyMonthlyEvery 4 days — better
AdsNo — betterYes
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.0 — better18.4
Further details — not scored
Size70 MB28 MB
Age rating4+17+
DeveloperS-IMSY LtdJiwon Park

In-app purchases

None

SIMSY

No in-app purchases

1 purchases

Walnut

One-time1
  • Remove Ads$3.99

Questions

Is SIMSY free?
SIMSY is free to download, with no in-app purchases.
Is Walnut free?
Walnut is free to download, with in-app purchases available.
Do SIMSY or Walnut have ads?
Walnut shows ads; SIMSY does not.
Which is updated more often, SIMSY or Walnut?
SIMSY ships an update monthly, and Walnut every 4 days. Most recently, SIMSY was updated on September 29, 2026 and Walnut on October 9, 2026.

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