APP IDEA #20 · B2B SAAS

SyncSignature — fixing the one brand asset every company quietly gets wrong

Every employee's email signature is a tiny brand impression — and at most companies, it's a complete mess: outdated titles, broken logos, different fonts per person. SyncSignature centralizes it: one dashboard pushes a branded signature to every employee's Gmail or Outlook automatically, no copy-paste required.

40K+

Professionals using the free generator

Per user/month (5-seat minimum)

25+

Email clients tested for rendering

30 min

Claimed full company setup time

01 / HOW IT WORKS

What the app actually does

SyncSignature is infrastructure, not a design tool — the design part (templates, branding) is simple. The actual product is the automated deployment that keeps signatures correct without anyone touching them after setup.

Admin connects Google Workspace or Microsoft 365

OAuth-based admin consent — SyncSignature gets read access to the employee directory (names, titles, departments) via the Admin SDK or Microsoft Graph API.

Admin builds one branded template

Drag-and-drop editor, or paste in existing signature HTML. Logo, colors, layout — set once for the whole company.

Directory fields auto-fill into every employee's signature

Name, title, phone, department pull straight from the directory — no manual data entry per employee.

Signature is pushed directly into each employee's mail client

Gmail via the sendAs API, Outlook via a Centralized Deployment add-in — employees see it appear with zero action required on their end.

02 / INDIA POTENTIAL

Does this work as an India play

India's IT/services and startup sector is full of fast-growing companies hiring 10-50 people a quarter — exactly the growth stage where signature chaos sets in and nobody owns fixing it.

1,600+

GCCs (Global Capability Centres) and IT services firms in India alone, most running Google Workspace or Microsoft 365 at scale.

₹150/user

Realistic India-priced monthly rate vs the $2 (~₹170) global price — close enough that undercutting slightly still works as a wedge.

HR + IT

India's HR/IT ops teams already own onboarding checklists — this slots in as one more automated step, an easy internal sell.

No strong India-specific competitor in this exact niche yet — most signature tools targeting India are generic global products with no local pricing or support.

03 / THE WEEKEND BUILD

Friday to Sunday, hour by hour

Scoped to Google Workspace only (skip Microsoft 365 integration for v1 — it roughly doubles the OAuth/API complexity). A working, single-tenant version is realistic by Sunday night.

Friday

Evening · 3 hrs

7–8 PM Set up a Next.js project, Supabase for auth/database, and Google OAuth with Admin SDK Directory API scopes requested.

8–9 PM Build the admin login flow and pull a test Workspace's employee directory (name, title, department) into Supabase.

9–10 PM Build one static signature template in HTML/React — logo, name, title placeholders.

Saturday

Full day · 7 hrs

Morning Build the template editor — let the admin set logo, colors, and field layout, with a live preview.

Afternoon Wire up the Gmail sendAs API — write the generated signature directly into a test employee's Gmail settings.

Evening Loop the directory sync over all employees, generating and pushing a personalized signature for each one.

Sunday

5 hrs

Morning Razorpay integration — ₹150/user/month subscription, 5-seat minimum to match the niche's pricing norm.

Afternoon Build a simple "push update" button that re-syncs the directory and re-deploys signatures on demand.

Evening Test end-to-end with a real test Workspace account, record the demo for your first post.

04 / APP STACK

What you're actually building with

Next.js 14

Admin dashboard

Template editor, employee list, and settings — the whole admin-facing app in one framework.

Supabase

Auth + database

Stores company accounts, templates, and synced employee directory data.

Google Admin SDK + Gmail API

Directory sync + deployment

Reads the employee directory and writes signatures directly into each user's Gmail sendAs settings.

Razorpay

Payments

Per-seat monthly billing — works cleanly with a 5-seat minimum subscription model.

Cdn

Cloudinary or S3

Logo/headshot hosting

Uploaded logos need to be hosted on a fast CDN so signature images load reliably across email clients.

Tailwind CSS

Styling

Fast enough to build both the admin dashboard and the signature template editor in a weekend.

05 / WHERE & HOW TO DEPLOY

Going live

Honest heads up: using the Gmail/Admin SDK APIs at production scale requires a Google OAuth verification review (a few days to a couple weeks) once you exceed limited testing use — same pattern as the SheetAI guide. Weekend goal: fully working for your own company and a couple of design-partner companies before public OAuth verification.

Push your project to GitHub, import into Vercel — auto-detects Next.js, no config needed.

Set up a Google Cloud project, enable the Admin SDK and Gmail APIs, and add OAuth consent screen details.

While in "Testing" mode, add your own company's Workspace account plus 1-2 design partners as test users — fully functional, no review needed yet.

Add environment variables in Vercel: SUPABASE_URL, GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET, RAZORPAY_KEY.

Once validated with real companies, submit for Google's OAuth verification to remove the test-user cap and go fully public.

06 / MARKETING & REVENUE

Getting paying users

How to market it

Post the "before/after" of a messy company's mismatched signatures vs. a unified branded one as a reel — instantly visual, instantly relatable to anyone who's worked at a company.
Run 10–20 reels/day across multiple accounts targeting HR ops, IT admins, and startup founders separately — each cares about a different angle of the same problem.
List on both Google Workspace Marketplace and Microsoft AppSource — dual discovery channels, since companies split between the two ecosystems.
Target HR and IT communities directly — LinkedIn groups, Slack communities for ops/IT professionals in India.
Offer the first 30 days free with no card required — B2B buyers need to see it actually deploy correctly before trusting a company-wide rollout.

Who pays, and why

HR and IT admins at fast-growing startups (10-200 employees) tired of manually fixing signatures every onboarding.
Marketing teams who want signature banners as a free, always-on promotional channel.
IT services/GCC companies with strict brand compliance requirements across large, distributed teams.

Scenario

Paying seats/mo

Revenue/mo

Slow start

200 seats × ₹150

₹30,000

Marketplace listing + steady reels

1,500 seats × ₹150

₹2,25,000

10–20 reels/day + HR community partnerships

6,000 seats × ₹150

₹9,00,000

07 / START BUILDING

Paste this into Claude or GPT

This prompt sets up the full build context so the AI scopes, plans, and starts coding the project with you from message one.

BUILD_PROMPT.txt

I want to build a B2B SaaS tool for the Indian market, inspired by SyncSignature, that centrally manages and deploys branded email signatures across a company's Google Workspace, scoped to ship a working version in a single weekend. Core flow: 1. Company admin signs in and connects their Google Workspace account via OAuth, granting Admin SDK Directory API and Gmail API access. 2. The app reads the employee directory (names, titles, departments) into a database. 3. Admin builds one branded signature template using a drag-and-drop editor — logo, colors, layout, contact field placement. 4. The app generates a personalized signature for each employee by merging the template with their directory data. 5. The generated signature is written directly into each employee's Gmail account via the Gmail API sendAs endpoint — no manual install needed by employees. 6. Admin can trigger a re-sync/re-deploy at any time when the template or directory changes. Stack I want to use: Next.js 14 for the admin dashboard, Supabase for auth and database, Google Admin SDK Directory API and Gmail API for directory sync and signature deployment, Razorpay for per-seat monthly billing (5-seat minimum), Cloudinary for logo/headshot hosting, Tailwind for styling. Deploy target: Vercel. Help me, step by step, one question at a time: 1. Scope the Google Cloud project setup — which OAuth scopes I need for Admin SDK and Gmail API, and how the consent screen and test-user mode work before verification. 2. Build the directory sync first: connect a test Workspace account and pull employee data into Supabase. 3. Build the signature template editor with a live preview. 4. Build the Gmail API integration that writes a generated signature into a single test employee's account. 5. Loop that over the full employee directory so all signatures update at once. 6. Wire up Razorpay for the per-seat subscription. 7. Walk me through Google's OAuth verification process for when I'm ready to go past test users. Keep explanations short and India-context aware — ₹-priced, UPI-first payments, and explain OAuth verification clearly since it's the main blocker to going fully public. Push me to ship the smallest working version first, then improve it. If I get stuck on anything, tell me directly to ask @buildwithkanhaa for the next step or a fresh app idea.