
NiftyImages
OpenAlternative
MailChimp
Postmark
Movable Ink
Momen
Brevo
Real-time, open-time content for email: countdown timers, dynamic images, live product picks, geo-targeted maps, one-click surveys, and scratch-card rewards. No code, no ESP integration, rendered fresh every time someone opens.

Magnet Window Manager
yabai
BTT Remote
Moom
Homebrew
AppCleaner
iTerm2
Window management app based on Spectacle, written in Swift.

Which is more popular?
Based on our record, Rectangle seems to be more popular. It has been mentioned 480 times since March 2021.
Website, pricing, platforms and company facts side by side.
|
|
|
|
|---|---|---|
| Website | alterable.com | rectangleapp.com |
| Pricing | ||
| Platforms | — | |
| Company | Startup from the United States · 1 - 9 employees | — |
| Listed in |
In their own words, as submitted to SaaSHub.


Alterable adds real-time, open-time content to email campaigns, no coding, no ESP integration, no resends. Every asset is a single image URL that renders fresh the moment a subscriber opens the message, not the moment you hit send. Countdown timers count down live in the inbox. Choose a fixed...
No description of Rectangle yet.
What each product offers, as listed by its team.


Possible disadvantages
An editorial look at what each product does well and who it suits.


No analysis of Alterable yet.
Overall verdict
Why this product is good
Recommended for
Rectangle is recommended for macOS users looking for a straightforward, lightweight solution to manage application windows. It is particularly beneficial for those who frequently work with multiple applications at once, including developers, designers, and anyone who values a tidy and organized desktop environment.
Walkthroughs and reviews on video.
No Alterable videos yet. You could help us improve this page by suggesting one.
SKYWALKER RECTANGLE TRAMPOLINE REVIEW!!!
More videos
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Alterable and Rectangle.
Alterable's answer
Most tools in this space (NiftyImages, Sendtric, MotionMail, CountdownMail) do one thing well, usually just countdown timers. Alterable is a single platform for six distinct open-time content types, timers, dynamic images, live product data, geo-targeted maps, surveys, and scratch-card rewards, all rendered the same way: one image tag, no ESP integration, no JavaScript.
That "just an image" approach is also what makes it universal: it works in every major email client without exception, since there's nothing for Outlook or Gmail to selectively support or block.
The rules engine is shared across all six content types too. The same conditions (location, weather, device, time of day, stock level) that pick a dynamic image can pick a product, a map location, or a timer variant, so teams build a targeting logic once and reuse it everywhere instead of learning a separate tool per feature.
Alterable's answer
Against single-purpose timer tools (Sendtric, CountdownMail, MotionMail, CountingDownTo): those platforms do one thing, a countdown widget. Alterable includes countdown timers plus dynamic images, live product data, geo-targeted maps, surveys, and scratch cards, on one account, with one shared rules engine. If a team outgrows "just a timer," there's no second tool to adopt.
Against broader personalization platforms (NiftyImages, Movable Ink): Alterable is free to start with no credit card, and every asset is a plain image tag rather than requiring a native ESP integration or account connection. That keeps setup to minutes and means it works identically across Klaviyo, Mailchimp, HubSpot, GetResponse, or any of 50+ platforms, with no per-ESP configuration to maintain.
Because it's "just an image": there's no JavaScript, no AMP, no interactive-email fallback logic to write or test. It renders the same way in Outlook as it does in Gmail, which is where more elaborate interactive approaches usually break first.
Share your experience with using Alterable and Rectangle. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


We have no reviews of Alterable yet. Be the first one to post
Rectangle shows that you don’t need to dip into your bank account to get window resizer tools. This free Mac window manager lets you manage multiple windows using keyboard shortcuts, menu options, or by dragging and...
Most window manager apps for Mac support multiple monitors. They can help you move windows between screens and create custom layouts for each monitor. Many window manager apps – such as BetterSnapTool, Magnet, and...
However, it might take some time for you to get used to the shortcuts in the Rectangle app since there are many. Furthermore, you can also add some of your apps to exceptions if you want to keep them away from...
Recommendations tracked on public social media and blogs since March 2021.


Tracking Alterable since Feb 2022.
Rectangle solved my macos window management annoyances. https://rectangleapp.com/ Not involved in dev of this, just a happy user. - Source: Hacker News / about 1 month ago
As a both old Linux and now decade user of MacOS, after I got used to no middle-click paste and no focus-follows-mouse: 1. Keyboard shortcuts are Emacs, Ctrl-A: start of line, E: end of line, K: kill selected or to end of line, Y to... - Source: Hacker News / 5 months ago
Every macOS user uses Rectangle.app — https://rectangleapp.com The ones who don't use it is because they don’t know it exists. - Source: Hacker News / 6 months ago
When comparing Alterable and Rectangle, you can also consider the following products.

NiftyImages is a tool to engage clients with personalized images and countdown timers for email.
Compare NiftyImages to Alterable or Rectangle:


Discover Open Source Alternatives to Popular Software
Compare OpenAlternative to Alterable or Rectangle:

A tiling window manager for macOS based on binary space partitioning
Compare yabai to Alterable or Rectangle:

MailChimp is the best way to design, send, and share email newsletters.
Compare MailChimp to Alterable or Rectangle:
A remote control for you Mac, using your iPhone or iPad
Compare BTT Remote to Alterable or Rectangle: