Due to Twitter's changes, to use Twitter with Simplified you need to bring your own API Key.
This will apply to both new and old connections. So if you're connecting a Twitter account for the first time, or if you already publish on Twitter via Simplified, you'll need to follow the steps in this article.
Here's how to set it up.
First Step: create a Twitter Developer account
If you don't have a Twitter Developer account, you need to set one up. (Don't worry it's free - for the most basic one (see note below)* - and it only takes a few minutes)
Go to https://developer.twitter.com and sign up for a free account.
Once on this page:
1 - select the Free plan
2 - click on Sign Up for Free Account
3 - complete the description, check the boxes, then click Submit.
You should get access to Twitter's Developer portal immediately.
Second Step: setting up an app + API Keys
On the left side menu of the Developer Portal, click the Products menu, then click the "Twitter API v2" project.
You'll see all features, the number of tweets per month, and an overview of the Free plan. You will be able to publish up to 1500 tweets per month, which covers scheduling and social inbox for most users.
Then, on the left side menu of the Developer Portal, click the Projects & Apps menu.
Click on the second project that will appear under Default project (the one that starts with your Twitter account name), on the left side menu.
Under User authentication settings, click the Set up button.
Set up your user authentication as follows:
Under App permissions choose Read and write.
Under Type of App choose Web App, Automated App or Bot.
Under App info add this URL in Callback URI / Redirect URL: https://app.simplified.com/oauth
Under Website URL you can add a link to your own website.
Now, on the top menu, click on Keys and tokens
On Consumer Keys (first option on the Keys and tokens screen), you will see the API Key and Secret section. This is what you need to connect your Twitter account to Simplified.
Click on the Regenerate button on the right side.
Confirm by clicking Yes, regenerate.
A window with your API Key and API Key Secret will open. Save these to add to Simplified, then click Yes, I saved them.
Then, set up your account with Simplified.
Third Step: setting up Twitter with Simplified
Click on Publishing on the left side menu, or Schedule Post on the Social Media Home.
Click on Add Account on the account list (or by clicking on the 3 stacked dots at the end of the upper list)
Enter your API Key and API Key Secret on the respective fields on this window
Click Authorize with Twitter
That's it!! Your Twitter account is now connected and ready to post!