From the MapInfo Pro 17.0.2 Release Notes:

Starting with version 17.0.2, MapInfo Pro users who register with an online account are able to run MapInfo Pro in a connected Viewer Only (subscription) mode. The MapInfo Pro installer adds a shortcut (Icon) to the Windows Start Menu to start MapInfo Pro in Viewer (subscription) mode. This icon is located next to the regular MapInfo Pro Start Menu shortcut.

In order to run the Viewer version of MapInfo Pro, an online account must be created. Users can do this from the MapInfo Pro Backstage Services Tab, when MapInfo Pro Viewer is first run.
Note:  which user is logged in can be changed at the Backstage Services Tab.
Capabilities and Limitations

When running MapInfo Pro in Viewer (subscription) mode, the user is connected to their account upon start-up. Each MapInfo Pro account is assigned to a Viewer subscription plan which identifies the set of features available to them in MapInfo Pro. Currently there is only one plan Viewer. In future, we may offer other free or paid plans with different levels of functionality. In addition, which features are available in each plan can change over time as features are added or removed from the plan.
MapInfo Pro Viewer supports all languages supported by MapInfo Pro.
Features and Limitations

· MapInfo Viewer (subscription) mode allows users to open and view any MapInfo Pro workspace (.wor) file. In addition users can open MapInfo .tab files and other supported formats (such as geopackage, csv, excel, sql server, postgis, etc.) in order to view and understand your data.

·  Editing of data is not supported (restricted). Saving of any changes to the workspace is also not allowed.

· Limited analysis is allowed such as queries, selections, browsing data, turning map layers on/off. Printing (and exporting to pdf) of Maps and Layouts are allowed.

Limited editing of Layout text and image frame are allowed before printing.

· Only a limited set of Tools are allowed to run. Running a MapInfo Pro Add-in or program (.mbx ) is prohibited.

· Bing basemaps and search functionality is only allowed if your organization has a Bing Key, which can be entered on the Backstage Licensing Tab.

· It is expected that some users will have a fully licensed version of MapInfo Pro and can create workspaces to share and be viewed by other users running only the MapInfo Pro Viewer.

· Technical Support for MapInfo Viewer is limited to installation issues. To contact support please Create a Support Case

Note: If running MapInfo Pro in Viewer (subscription) mode, users cannot opt-out of the Customer Experience Program and this feature will be turned on by default. If user is running a normal licensed copy of MapInfo Pro then the Customer Experience Program is optional and may be turned on or off from the backstage (Pro Tab, Options, Application Preferences).
Note: MapInfo Pro 17.0.2 64-bit will install both Pro 17.0.2 full version and the 17.0.2 Pro Viewer version.
Starting with MapInfo Pro 17.0.3, users can choose to install just the full version, just the Pro Viewer or both versions.