Comparison

Gapfy Echo vs Knockbox

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

Head to head
About

Gapfy Echo

Features
Read full description

Gapfy Echo is an API client for iPhone and iPad. Build and send HTTP and REST requests from your phone, read the response with syntax highlighting, and keep your work organized in spaces, collections and environments. Requests you create in the app are HTTP, with nine methods to choose from: GET, POST, PUT, DELETE, PATCH, HEAD, OPTIONS, TRACE and CONNECT. GraphQL, WebSocket, Server-Sent Events and gRPC unary requests are authored in the Gapfy Echo desktop app and run here once they sync down. A WebSocket or Server-Sent Events session returns its full transcript in the response body when it ends. What you can do - Send HTTP and REST requests with query parameters, headers, a body and auth, and switch a single parameter or header off without deleting the row - Authenticate with a Bearer token, Basic username and password, or an API key sent as a header or as a query parameter - Cancel a request while it is still in flight - Check the status code, duration, time to first byte and payload size at a glance, and open the full response headers when a header is what you are debugging - Read the body with syntax highlighting, flip to raw text, or copy the whole payload to the clipboard; JSON is pretty printed for you - See pass and fail assertion results and script console output for requests whose scripts were written on the desktop - Create spaces, collections and nested folders from the app - Keep reusable values in environments, mark a variable as secret so it stays masked until you reveal it, and change the active environment straight from the send bar - Write {{variable}} placeholders in the URL, headers, parameters, body and auth fields, resolved from the active environment at send time - Open collections that teammates share with you, read only or with edit access, depending on what they granted - Search your run history by URL, narrow it to 2xx, 4xx-5xx or errors, and tap any run to reopen the request behind it - Pick up where you left off from the ten most recent runs on the Home tab - Choose a system, light or dark theme with one of ten accent colors - Use the app in English, German, Spanish, French or Portuguese - On iPad and in landscape, the request list sits beside the editor, and a request opened full screen shows its response in a column of its own Requests save themselves as you type, so a send always uses what is on screen. Signing in is optional. In guest mode the app works with no account and no network, and everything stays on the device. Sign in with a Gapfy account and your spaces, collections, requests and environments sync with the Gapfy Echo desktop app, so an endpoint you set up at your desk is ready to send from your pocket. Pull down on Home, Collections or Environments to sync, or use Sync now in Settings. An account that belongs to more than one workspace can switch between them there. Run history is written on the device only and is never uploaded. The local database is encrypted on the device, with the key held in the keychain. Gapfy Echo is a module of the Gapfy platform.

About

Knockbox

Read full description

Knock once, and your phone buzzes. Knockbox turns one HTTP request into a push notification on your iPhone. Anything that can send a request can reach you: a deploy script, a cron job, a monitoring check, a CI pipeline, or a coding agent that has just finished a long task. If it needs your go-ahead before continuing, it can wait for your answer. curl -d "Build finished" https://your-server/api/v1/send/YOUR_TOKEN THE SERVER IS YOURS Knockbox is the client for a server you control. The server is open source and runs on a VPS, a NAS, or a Raspberry Pi at home. It holds its own Apple push key, so a notification goes from your machine to Apple and then to your phone, without passing through anyone in between. If you would rather not run anything, open knockbox.miramiao.com on your iPhone and you are connected — no sign-up, no password. WHAT A MESSAGE CAN CARRY • A Markdown body with headings, lists, links and syntax-highlighted code. • Images, shown in the notification and kept with the message. • Long text. The body is fetched as the notification lands rather than packed into it, so there is no length limit to work around. • A title, a channel, and an interruption level: quiet, normal, or time sensitive when it has to break through Focus. REPLIES • The sender can attach a set of options, or allow a free-text answer. • Answer from the message itself. Your server posts the reply back to the address the sender gave, signed, and the sender takes it from there. • The sender can set a deadline. After it passes the message reads "Reply window closed" and the server stops accepting — you are never left thinking an answer went through. • A message is answered once, and the answer is the same across your devices. CHANNELS • One token per channel, so a noisy monitor and a personal reminder stay apart. • Muting a channel truly stops it: the mute lives on the server, so nothing is sent at all. • Search your history, mark as read, delete a message, or clear a channel. Deletions are real, on the device and on the server. MORE THAN ONE DEVICE Pair a second iPhone or iPad from a device that is already connected. Both receive everything and share read state. TRY IT WITHOUT A SERVER Demo mode fills the app with example messages and sends a sample notification, so you can see how it works before setting anything up. FREE, AND THAT IS ALL No ads, no analytics, no account with us, no in-app purchase, no subscription. The app is free and the server is open source. Server source code: https://github.com/aichy126/knockbox Public server: https://knockbox.miramiao.com How to send: https://knockbox.miramiao.com/docs Questions: info@miramiao.com

Screenshots

Gapfy Echo4 screens
Knockbox4 screens

Verdict

The call

The clearest difference is update cadence: Knockbox at daily against Gapfy Echo's every 2 weeks. Gapfy Echo's advantage is device support (4 vs 2) and iOS requirement (15.0 vs 17.0). On price, ads and in-app purchases there is nothing between them.

Scored on Price Ā· Rating Ā· Positive reviews Ā· Number of ratings Ā· Update frequency Ā· Ads Ā· In-app purchases Ā· Monetization Ā· Best chart rank Ā· Devices Ā· Requires iOS

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

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

UpkeepUpdate frequency

Gapfy Echo ships an update every 2 weeks, Knockbox daily. The most recent releases landed on October 31, 2026 and November 6, 2026 respectively.

Scorecard3 real differences Ā· 3 level
Gapfy Echo versus Knockbox: the parameters behind the verdict, then further details
ParameterGapfy EchoKnockbox
PriceFreeFree
Update frequencyEvery 2 weeksDaily — better
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad
Requires iOS15.0 — better17.0
Further details — not scored
Size100 MB7 MB
Age rating4+4+
DeveloperGAPFY UNIPESSOAL LDA苗 苗

In-app purchases

None

Gapfy Echo

No in-app purchases

None

Knockbox

No in-app purchases

Questions

Is Gapfy Echo free?
Gapfy Echo is free to download, with no in-app purchases.
Is Knockbox free?
Knockbox is free to download, with no in-app purchases.
Do Gapfy Echo or Knockbox have ads?
Neither Gapfy Echo nor Knockbox shows ads.
Which is updated more often, Gapfy Echo or Knockbox?
Gapfy Echo ships an update every 2 weeks, and Knockbox daily. Most recently, Gapfy Echo was updated on October 31, 2026 and Knockbox on November 6, 2026.

Other comparisons