chromeparental.berta.one
Chrome Parental Control
Chrome and Chromebook extension: site blocks, daily time limits, schedules, activity logs with export, and mobile admin. Free tier plus a £20 lifetime Premium upgrade.
Visit →Berta Atelier — apps
Browser extensions, hand-built.
Chrome and Chromium extensions to the same Atelier standard. Five are already live in our portfolio — Chrome Parental Control, Cognitive Ledger, Prompt Firewall, Image Format Converter, and Markdown Editor by Berta — all Manifest V3, all local-first by default, with paid tiers where the product needs them.
Mobile apps (Android / iOS) are not on offer yet. We will only sell what we have already shipped in-house.
In-house extensions — the proof
These extensions ship as Manifest V3, local-first by default, with paid tiers and privacy-posture pages on their marketing sites where applicable.
cognitiveledger.berta.one
Cognitive Ledger
Chromium Manifest V3 session ledger: domain switches, fragmentation indices, inferred intent, JSON export, daily insight. Free install plus a £9.99/year supporter tier.
promptfirewall.berta.one
Prompt Firewall
Local prompt scanning on supported AI chat pages before send: secret and PII-style patterns, redaction workflow, optional Premium sanitise to your own API endpoint. No Prompt Firewall backend.
ifc.berta.one
Image Format Converter
Chromium Manifest V3: convert images locally to PNG, JPEG, WebP, or AVIF from the toolbar popup or a full-window batch queue—Canvas-based, no uploads, no account. Same experience as the companion web app.
md.berta.one
Markdown Editor by Berta
Chromium Manifest V3: split-pane Markdown with live preview, multi-document sidebar, optional new-tab surface, toolbar popup, exports to .md / .html / print—autosave to chrome.storage.local, no network, no account.
Extension tiers
Three tiers covering everything from a single-popup utility to a paid, server-backed extension with telemetry. Each tier is the smallest engagement that fits — if your brief sits between two we will recommend the cheaper one.
Tier 1
Sprout
£495 one-off · £15/mo care
5–7 working days · 1 round of revisions
Best for: a single-feature browser utility — popup, content script, local storage. The "I want one button that does X" extension.
- Manifest V3, Chrome and Chromium
- One feature: popup, content script, or context menu
- Local storage only (no backend)
- Icons in 16 / 32 / 48 / 128 px
- Privacy-by-default copy and a one-page README
- Optional £15/mo care: store-review patches, security updates
Tier 2 — most common
Branch
£1,495 one-off · £15/mo care
2–3 weeks · 2 revision rounds
Best for: an extension with multiple features, an options page, JSON export, and an optional supporter tier. The Cognitive Ledger shape.
- Everything in Sprout
- Options / settings page
- Background service worker with persistent state
- OAuth or API-key entry for third-party services
- JSON / CSV export and import
- Optional Stripe supporter tier (one-time or yearly)
- Chrome Web Store listing assets included
- £15/mo care: store-review patches, MV3 changes, monthly security updates
Tier 3
Canopy
£3,495 one-off · £29/mo care
4–6 weeks · 3 revision rounds
Best for: a paid-tier extension with server-backed sync, telemetry, and multi-browser packaging. The Chrome Parental Control shape.
- Everything in Branch
- Free / paid tier with Stripe checkout and license keys
- Server-backed sync (your existing API or a small Node / FastAPI backend)
- Privacy-respecting telemetry with opt-in
- Multi-browser package (Chrome / Edge / Brave / Opera)
- Optional Firefox port quoted on top
- Privacy-posture marketing page on your domain
- 30-day defect window post-launch
- £29/mo care: store-review patches, MV3 changes, dependency updates, monthly security audit
Add-ons
Bolt-on units priced as fixed work, not time and materials. Mix into any tier.
Chrome Web Store listing
Listing copy, icon, screenshots, promo tile, store-policy review, and submission. Included in Branch and Canopy.
£195
Manifest V2 → V3 migration
Audit your existing extension, migrate to MV3 service workers, declarative net-request rules, and re-publish.
£495
Stripe / paid-tier flow
Stripe Checkout, licence keys, customer portal, supporter tier, lifetime licences. Included in Canopy.
£495
Multi-browser package
Edge, Brave, Opera packaging from a Chromium build. Firefox MV3 port quoted separately. Included in Canopy.
£295
Firefox MV3 port
Manifest reshape, polyfill review, AMO submission, and review-feedback handling.
£695
Backend bundle
Node or FastAPI server with auth, DB, and a small admin surface — sized for an extension's sync and licence-check needs.
From £1,495
Privacy-posture marketing page
One-page landing matching your house style, with install button, free vs paid breakdown, and a clear data-handling table.
£450
Crash reporting + analytics
Sentry or Firebase Analytics with privacy-respecting defaults and a data-retention plan.
£195
OAuth + identity provider
Google, GitHub, or your own SSO; in-extension token handling done correctly.
£395
The Atelier standard for extensions
Manifest V3, no shortcuts
All builds ship as Manifest V3 service workers from day one. We do not ship anything on the deprecated MV2 surface, even when it would be faster.
Local-first by default
If your extension can work without a backend, it does. State lives in chrome.storage.local with a clean schema and an export path. Backends are added only when sync, paywall, or telemetry actually require them.
Privacy posture, in writing
Every extension ships with a data-handling table on the marketing page and a privacy notice that matches what the code actually does. No "we may collect…" generic copy.
Store policy, on first submission
We read the Chrome Web Store program policies and write the listing to match before submission. Single-purpose, narrow permissions, and a justification for each host_permissions entry. Rejection costs everyone a week — we avoid it.
Operational handover
You receive the source repository, store-listing assets, signed CRX (where applicable), an editor's manual for non-technical updates, and a 30-day post-launch defect window.
Not yet on offer
Mobile apps (Android, iOS)
We have shipped five browser extensions in-house but no mobile applications yet. Until we do, we will not sell mobile build engagements. If your brief truly requires a mobile companion, we will refer you to a partner studio rather than learn on your budget.
Firefox-first
Firefox MV3 ports are an add-on, not a primary tier — most of our delivery experience is on the Chromium surface.
Enterprise distribution
Group Policy-managed deployment and on-premise extension hosting are quoted bespoke and only after the standard build is complete.
Brief an extension
Send a paragraph describing what your extension should do and which existing tool it might replace or supplement.