Apps similar to Tab Display include Spacedesk, which has a free version. Other options are Side Screen, Deskreen, Duet Display and EasySwitch. You can choose from more than 10 Screen Mirroring Apps like Tab Display for Mac, Windows, iPad, iPhone and Android.
Turn your iPad/iPhone or Android tablet or smartphone into a convenient side monitor for your Windows or Mac desktop. iDisplay is a universal app specially optimized for iPad, iPhone, iPod Touch, and Android devices screens.
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Smart devices become monitors by connecting them to a PC via USB! The Convenient Connect TwomonUSB
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Turn any Mac you already own — even an old iMac — into a true extended second display for your Mac. No dongle, no subscription, no account, no cloud.
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BetterCast lets you use your old device (Mac, Android, iPhone) as real extended displays with zero subscriptions, zero cloud, and native macOS performance.
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MirrorHall creates virtual second monitors over the network using UDP video streaming among Linux desktop or mobile devices. It is optimized for low latency, and is based on gstreamer and GNOME's mutter screen sharing APIs.
