Paymo: Collaborate together in teams to get results

Paymo has the following native integrations available:
Google: Sign in and sign out with this integration and even add files from google drive to Paymo on either task or project level to keep updates and context and save on storage.
Google Calendar: User can stay updated by letting this integration sync all their Paymo tasks to Google Calendar.
Zapier: When user integrate Paymo to this they will be able to connect Paymo with more than 1,000 apps.
Slack: Helps you to stay in touch with your team instantly. Can also stay on discussion without leaving your channel.
QuickBook Online: With this integration you can keep your accounting in check and export invoices. You can also register payments and sync them back to Paymo .
Xero: Helps to have cash flow in sight and exportin invoices to Xero together with all taxes
Typeform: allows user to engage their audience through customizable forms that require zero coding.
Jotform: Create professional-looking forms without a single line of code. Once form is submitted, this integration helps colleagues and clients to create projects, tasks and upload files in Paymo.
Intergromat: Allows you to connect with apps and automate your work
Pabbly: allows user to connect with the apps that they use and automate their work.
Pomodone: With this integration user can work fast within 25 minutes and block any interrupting websites to focus on your to-dos in a fun yet productive manner.
Lambdatest: allows user to test the responsiveness of website or app across different web browsers and screen sizes and push bugs into Paymo.
Rethink: Help syncs all the files from the desktop, cloud apps, and tools you already use in one place.
Grandtotal: allows user to track work in Paymo and then invoice that time with GrandTotal. User will be able to keep track of outstanding payments, while detailed graphs and stats give insights into the current state of the business.
Shift: allows you to streamline your workflow across your favorite apps. Users will be able to check emails and manage tasks in once interface.

Below we have our info of API options for Paymo

API Auth Methods:
OAuth2|API Key|Access Token

API WSDL Support:HTTP|SOAP|JSON
API Objects Accessible:The API from Paymo is well documented and what we like to see with cloud solutions, We feel like we repeat this a little, but as developers ourselves. We understand the importance of having an API reference for other developers to use. It also maintains good practices internally.

The current API endpoints for Paymo are:

Bookings (Resource Scheduling)
Client Contacts
Clients
Comments
Company
Discussions
Estimate Templates
Estimates
Expenses
Files
Invoice Templates
Invoice Payments
Invoices
Milestones
Project Templates
Project Statuses
Projects
Reports
Subtasks
Sessions
Task Lists
Task Recurring Profiles
Tasks
Time Entries
Users
Task Assignments
Workflows
Workflow Statuses

And for the Webhook listeners. Here are the events that can be hooked:

model.insert.Client
model.update.Client
model.delete.Client
model.insert.Project
model.update.Project
model.delete.Project
model.insert.Tasklist
model.update.Tasklist
model.delete.Tasklist
model.insert.Task
model.update.Task
model.delete.Task
model.insert.Invoice
model.update.Invoice
model.delete.Invoice
model.insert.Entry
model.update.Entry
model.delete.Entry
model.start.Entry
model.stop.Entry
model.insert.Milestone
model.update.Milestone
model.delete.Milestone
model.insert.Report
model.update.Report
model.delete.Report
API Cost:Free/Part of Existing Subscription
API Version:1
You can also have a good read of theAPI Documentation Here