Stackブラウザ alternatives: what you can drop

Looking for an alternative to something usually means one of two different things. Either the product is gone and a replacement is mandatory, or the product still works and the question is whether something else would fit better. For Stack, the situation is the second one. The site is live, the pricing page is up, and the roadmap describes work in progress. So the useful question is not what replaces it. The useful question is which of the things it does are actually holding the day together, because the answer decides how much a replacement has to cost.

What Stack provides, as published

Stack describes itself as a spatial browser and organises pages as cards rather than tabs, laid out in a spatial environment. The published feature list includes keyboard-first navigation, compatibility with Chrome extensions, multiple customisable profiles, and a multiplayer capability marked as coming soon. The product is listed on WeFunder, which lets users become shareholders.

The pricing page has three entries:

Plan	Price	What it includes
Starter	Free forever	Browsing essentials, unlimited profiles, 5 Flows, 3 color themes
PRO	$144 per year or $15 per month	Unlimited Flows, 11 color themes, live collaboration marked coming soon
PRO Lifetime	$199, reduced from $864	Everything in PRO plus exclusive cursors, an NFT-linked license, and Stacker perks

Two details on that page are worth noting because they change how the options read. The Lifetime tier is described as sold out of 4242 Lifetime Licenses, so it is not a currently purchasable route for someone arriving today. And the roadmap language describes a rebuild completed in December using native technology, with the next milestone being a fully functional single-player browser including extensions, a password manager, and a download manager. That is a product still filling in foundations rather than one that has finished.

None of this is a verdict. It is the shape of what a person is deciding to keep or leave.

Which parts of it are load-bearing

Products in this category bundle two separate things, and most people only depend on one of them.

The first is account and app separation. One storage area per identity, so a client's Google account and a personal one never collide, extensions are scoped, and cookies stay where they belong. This is the part that, when removed, causes visible failures within a day.

The second is spatial organisation: cards on a canvas, arranged by hand, with position carrying meaning. This part is a working style. Some people build a map of a project and navigate by memory of where things sit. Others open the same six apps every morning and never move anything.

Deciding which of the two is load-bearing takes about a minute of honest observation. If the canvas is rearranged weekly and the layout is part of how a project is thought about, the spatial model is the product. If the canvas has not moved since setup, the separation is the product, and the canvas is scenery. Almost every alternative below handles separation. Very few reproduce a spatial canvas, and paying for a canvas nobody moves is the most common mistake in this switch.

Flows, themes, and the free ceiling

On the free tier the practical limits are 5 Flows and 3 color themes, with profiles unlimited. If the setup has never exceeded five Flows, the paid tier is buying collaboration that is still marked coming soon plus eight more colour themes. That is a legitimate purchase if the roadmap is what is being backed, and it is worth being clear that is what the money is for.

What has happened elsewhere in this category

Two reference points from the last eighteen months are useful, because both involved products that were working fine on the day the news landed.

The Browser Company stopped active development of Arc in May 2025, stating that for most people Arc was too different, with too many new things to learn, for too little reward. Arc still receives Chromium security updates and has no announced shutdown date, and the company was acquired by Atlassian in October 2025 for $610 million, with the team now working on Dia.

Sidekick, a Chromium browser built around workspaces and a sidebar of web apps, was acquired by Perplexity in May 2025 and sunset on August 3, 2025. Its former address now redirects to Perplexity's Comet.

The point is not that any particular product is at risk. The point is that in this category the exit is usually an acquisition rather than a slow decline, and the warning period is measured in weeks. That argues for choosing a replacement whose data is easy to reconstruct: bookmarks that export, extensions available from the Chrome Web Store, and no state that exists only inside one vendor's canvas.

What a short warning period means in practice

Arc and Sidekick took different paths after the news. Arc stayed installed and functional, which meant no emergency for its users and no reason to move quickly. Sidekick had a date, and everyone using it had to have moved by it. Both outcomes are survivable, and both are much easier when the setup can be described on a single page: which identities exist, which apps belong to each, and which extensions are required.

Writing that page down is worth doing regardless of which tool is in use. It is the difference between a migration that takes an afternoon and one that takes a fortnight of remembering what was configured where. It also makes evaluating a new tool faster, since the page becomes the checklist the candidate is tested against.

The alternatives, with published prices

Prices as of September 2026, taken from each vendor's own pricing page.

Tool	Free tier	Paid	Platforms
Ferdium	Whole app, Apache-2.0 licensed	None	macOS, Windows, Linux
Browser profiles	Built into Chrome, Safari, Firefox	None	macOS, Windows, Linux
Rambox	Unlimited apps, up to 2 instances per app, 2 custom web apps	$7.00 per month or $70.00 per year, Teams at $14 per user per month with a 5 user minimum	macOS, Windows, Linux
Wavebox	Basic plan after a 7 day Pro trial	$8.33 per month paid annually, Teams at $12.50 per user per month	macOS, Windows, Linux
Shift	5 Spaces, 10 apps per Space	$199.99 per year	Desktop

Ferdium sits at one end, community maintained and free of any account requirement:

All your services in one place, built by the community Source: github.com

Rambox and Wavebox occupy the middle, both offering a free tier that is usable rather than a trial, with the paid tier adding unlimited instances and account-level features. Shift starts free at 5 Spaces with 10 apps per Space and prices its Advanced tier annually, which is a different commitment shape to a monthly plan. A side-by-side of those trade-offs is set out in Compared with Shift and Compared with Ferdium.

The axis that actually separates them

Pricing differences in this table are smaller than they look, since the gap between $70 and $144 a year is under six dollars a month. The real separation is structural. Ferdium and Rambox descend from the same open source lineage and treat a service as a configured web view inside a list, which keeps memory use predictable and makes adding an unlisted service straightforward. Wavebox is built on Chromium and behaves more like a browser that happens to group things, which is why extension support and link handling are stronger there and why it is heavier. Shift organises around Spaces holding a set of apps, which suits someone whose boundary is a client rather than a single account.

Matching that structure to the boundary drawn earlier matters more than the monthly figure. A person separating by identity wants the Spaces model. A person running many single-account services wants the list model. Paying more for the wrong structure produces a tool that is fought with daily.

Browser profiles remain the option people skip because they are free. They are a genuine storage boundary and they cost nothing to test, which makes them the correct control group for any paid decision.

What can be dropped, and what cannot

Things that usually turn out to be droppable: the spatial canvas itself for anyone who has not rearranged it in a month, colour themes beyond enough to tell windows apart, lifetime licensing as a concept, and any capability still marked as coming soon, since planning around unreleased features means paying today for a decision that can be made later.

Things that turn out not to be droppable: extension support, because password managers and ad blockers are usually load-bearing and an app without extension support forces a workaround on day one. Keyboard navigation, because anyone used to reaching an app in one chord finds mouse-only switching intolerable within a week. And per-account separation, which is the whole reason the category exists.

One more item belongs in the not-droppable list and is easy to forget: the specific web apps in daily use. Aggregation tools ship a catalogue, and an internal tool or a regional service may or may not be in it. Checking a list such as Supported apps against the actual daily set takes five minutes and prevents the most annoying discovery, which is finding out after migrating.

How to test a replacement in one week

Install the candidate alongside the current setup rather than instead of it. Move one identity across, ideally the busiest one, and leave everything else where it is. A partial migration gives a real comparison; a full migration gives a stressful week and no data.

Then measure three things. How many seconds it takes to reach the app that is needed most often. Whether the origin of a notification is identifiable without clicking. And whether anything from the old setup had to be recreated by hand, which is the cost that gets underestimated every time.

Resist the urge to tune the new tool during the test. A setup that only performs well after two evenings of configuration will perform badly again the next time an account is added, and the test is supposed to reveal that rather than hide it.

At the end of the week, either the busiest identity has stayed on the new tool without effort, or it has not. That result is more reliable than any feature comparison, and it costs nothing beyond the trial period. Free tiers and trial lengths are set out on each vendor's own Pricing page and are usually long enough for this.

What to change first

Answer the canvas question before comparing anything, because it splits the field in half and removes most of the shortlist. If the spatial layout is not the thing being used, test a free option first, since browser profiles and Ferdium cost nothing and settle whether a subscription is needed at all. If the daily set includes several accounts on the same service, SpaceDeck is one of the macOS options built around that case.