Shopping Chrome extensions have a privacy problem most users don't realize. Popular "deal finder" and "coupon" extensions are typically free because their business model is selling your browsing data — every site you visit, every product you look at, every cart you abandon, packaged and sold to data brokers and advertisers. A few have been caught doing worse, including redirecting affiliate commissions away from creators you were trying to support.
The category covers real, useful functionality: price tracking across stores, automatic coupon application, wish-list management, currency conversion, sale-alerting, and product comparison. The functionality is fine. The business model is the problem.
A custom-built shopping extension does the same job without selling your data. It tracks prices in your private browser storage. It applies coupons you've manually saved. It alerts you about sales you signed up to be alerted about. Nothing leaves your machine unless you choose. The tradeoff is you build the database of coupons or product feeds yourself — but for the items you actually care about, that's 10 minutes of input for permanent benefit.
More shopping extensions coming soon.
Watch products across sites, alert on drops, log price history
Auto-apply manually-saved coupon codes at checkout
Save products from any site to a personal wish list with notes
Side-by-side product comparisons, currency conversion, shipping calculators
The popular free coupon extensions are funded by either selling browsing data or by hijacking affiliate commissions from the creators whose links you click. A custom build does the coupon-application functionality without any of that — your browsing data stays on your machine, and creators get their full commission.
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Coupon-finding accuracy depends on the coupon database, not the extension. Most free coupon tools share the same crowdsourced databases. You can wire your custom extension to those databases (where APIs exist) or build a smaller, manually-curated database of coupons for your specific frequent stores — which tends to be more accurate than crowdsourced ones.
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Yes. Amazon doesn't expose a public price API, but the extension can scrape the price from a product page when the user visits it, store it locally, and compare against future visits. For passive monitoring without visiting, you'd need a server-side scraper — PlugThis can wire a basic cron-style backend if you want this.
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No, as long as it's scoped to specific sites (the stores you shop at) rather than running on every page. PlugThis output is Manifest V3 compliant and uses scoped content scripts — performance is identical to native Chrome.
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Tab managers, focus tools, note capturers, and time trackers that make your browser work harder for you.
AI-powered summarizers, writers, readers, and assistants — built on your own API keys, owned outright.
Highlighters, note-takers, web clippers, and research workflow tools — built around how you actually study and gather information.
Describe what you want in one sentence. PlugThis generates a working Manifest V3 Chrome extension in under two minutes.
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