Digital Signature Solution Integrated with Google Sheets

Sell products directly through Google Sheets with payment processing and inventory tracking.

Organize and manage customer information with portals, activity tracking, and relationship management.

Create invoices and process payments with automated reminders to get paid faster.

Stop Wasting Hours Searching Across Spreadsheets

Everything syncs to your Google Sheet. No more copy-pasting.

  • ✓ Development: Only $25/Screen
  • ✓ Ready in 7 days
  • ✓ No code required
  • ✓ Google Sheets as your database
  • ✓ No developers needed

✓ Trusted by 100+ businesses • No coding required

Get Your Free Custom Plan

Who will use this app (other than admin)?

  • Select one...Customers, Employees, Contractors, Suppliers, Volunteers, Donors, Students, Attendees, Applicants, Patients, Other

How many Them?

  • Under 500, 500+

What key tasks do they need to perform?

  • Select options...
    • Pay invoices or bills
    • Place orders or make purchases
    • Sign documents or contracts
    • Register for events or classes
    • Submit applications
    • Fill out forms or surveys
    • Submit for approval
    • Track tasks or project progress
    • Log activities or time
    • Schedule or book appointments
    • Upload files or documents
    • Manage their account
    • Other

Describe the journey of the Admin and Them — stage by stage, from the start of a task to its completion.

Your email address

How It Works

  1. Give Us 10 Minutes. We'll Plan Your App.

    • Submit: A short questionnaire about who will use the app and their journeys to complete their tasks
    • Receive (within 2 days): Screen-by-screen mockups, plus detailed role journeys for admin and all users
    • Review: One round of comments, then we finalize the plan

  2. We Build Your App

    • We turn your approved workflow and screens plan into a fully functional working app.
    • Timeline: Typically one week

  3. You Test Your App

    • You test the app on our Google Sheet. We fix all bugs and minor app definition adjustments with no limits.

  4. We Help You Deploy the App

    • After all tests pass, we copy the app to your Google Sheet.
    • Support: We guide you step-by-step through the Google Apps Script deployment process

  5. Use Your App

    • Using the Google web app URL, you access the admin portal with full control.
    • User Access: The app automatically sends token URLs to each user for their personalized portals and screens.
    • Automation: Everyone's actions update your Google Sheet automatically in real-time.

What You Get

  • Google Sheet with app-level power

    • Fully customized to your workflow
    • Give partners their own portals to execute their operations, driven and tracked from your sheet
    • Let others collaborate on your data without exposing your full sheet
    • Send payment requests from Google Sheets and track incoming payments
    • Collect signatures without DocuSign

  • Turn forms into automated workflows

    • Forms auto-update when your sheet changes
    • Forms can update existing records, not just create new rows
    • Forms in a Multi-step workflow adjust to answers in previous steps

  • Collaboration Without the Chaos

    • Custom views for different user types
    • No risk of broken formulas or accidental deletions
    • Multiple people can update their information at the same time

  • Risk-Free Development

    • We help you plan exactly what you need before building
    • Built on proven, maintainable code
    • Unlimited bug fixes included
    • Transparent, flat-rate pricing

  • Affordable Custom Apps

    • $25 per screen (includes 2 revisions)
    • $5-45 per month support
    • Working app ready in one week
    • Your data is always accessible in your Google Sheet
    • No vendor lock-in—standard JavaScript any developer can maintain

  • Save Time

    • Delegate data entry to the right people
    • Automated workflows and notifications
    • Validation prevents errors
    • Never miss process steps

  • Easy to Adopt

    • Fully customized to your workflow
    • Familiar Google Sheets interface
    • Free templates available
    • Full mobile functionality

Simple, Transparent Pricing

For Gmail Accounts (@gmail.com)

$5/month

  • ✓ Template Fees: $0
  • ✓ Tailored App Development: Schedule Consultation (starting at $25/screen)
  • ✓ Support: Email
  • ✓ Free Trial: 2 Month
  • ✓ Payment processing via Stripe — no extra fees

Google Workspace (@yourcompany.com)

$45/month

  • ✓ Template Fees: $0
  • ✓ Tailored App Development: Schedule Consultation (starting at $50/page design)
  • ✓ Support: Phone, Email
  • ✓ Free Trial: 2 Month
  • ✓ Payment processing via Stripe — no extra fees

What You Can Build

  • Sales and Inventory Tracking
  • Invoicing and Billing
  • Payment Collection
  • Expense Tracking
  • Customer CRM
  • Supplier Portals
  • Team Collaboration
  • Time Tracking
  • Employee Onboarding
  • Document Signing
  • Event Registration
  • Workflow Automation
  • Resource Scheduling
  • Volunteer Coordination
  • Donor Relations
  • Project Tracking

FAQ - Frequently Asked Questions

What is Centask?

Centask builds custom apps that automate your business processes using Google Sheets as the database. We transform your Google Sheets into powerful business applications.

Do I need coding experience?

No. We build the app for you. You just describe your workflow or choose a template, and we handle all the technical development.

How does the process work?

  1. You choose a template or describe your workflow, 2) We build your app, 3) You test it, 4) We deploy it to your Google Sheet, 5) You start using it with your team.

How long does it take to build an app?

Template-based apps can be ready in days. Custom apps typically take 2-4 weeks depending on complexity. We'll provide a timeline during consultation.

What types of apps can I build?

You can build apps for customer management, invoicing, payments, document signing, team management, inventory tracking, and much more.

What if I need changes after the app is built?

We offer revision packages. You can also customize using our JavaScript libraries or schedule additional development.

Can I customize the app later?

Yes. You have access to Centask libraries in Google Apps Script to customize at no charge.

What's included in the monthly subscription?

The subscription covers hosting, support, and access to updates. Template fees are one-time. Custom development is priced separately.

Are there fees for processing payments?

No. Payments are processed securely through Stripe, and you only pay Stripe's standard rates. There are no Centask fees for payment processing.

Is my data secure?

Yes. Your data stays in your Google Sheet, protected by Google's security.

Do I own the app?

Yes. The app is built in your Google Sheet using Google Apps Script. You own everything - the code, the data, and the app functionality.