Overview
Both checkboxes and switches use the .custom-control class as a
wrapper. They also both use <input type="checkbox"> and
have a <label> with a class of .custom-control-label.
Switches add the .custom-switch class to their .custom-control wrapper.
<div class="form-group">
<div class="custom-control custom-switch">
<input type="checkbox" checked class="custom-control-input" id="exampleSwitch1">
<label class="custom-control-label" for="exampleSwitch1">Switch</label>
</div>
<div class="custom-control custom-switch">
<input type="checkbox" class="custom-control-input" id="exampleSwitch2">
<label class="custom-control-label" for="exampleSwitch2">Switch</label>
</div>
<div class="custom-control custom-switch">
<input type="checkbox" disabled checked class="custom-control-input" id="exampleSwitch3">
<label class="custom-control-label" for="exampleSwitch3">Disabled</label>
</div>
<div class="custom-control custom-switch">
<input type="checkbox" disabled class="custom-control-input" id="exampleSwitch4">
<label class="custom-control-label" for="exampleSwitch4">Disabled</label>
</div>
</div>Inline
<div class="form-group">
<div class="custom-control custom-switch custom-control-inline mr-4">
<input type="checkbox" checked class="custom-control-input" id="exampleSwitchInline1">
<label class="custom-control-label" for="exampleSwitchInline1">Switch</label>
</div>
<div class="custom-control custom-switch custom-control-inline mr-4">
<input type="checkbox" class="custom-control-input" id="exampleSwitchInline2">
<label class="custom-control-label" for="exampleSwitchInline2">Switch</label>
</div>
<div class="custom-control custom-switch custom-control-inline mr-4">
<input type="checkbox" disabled checked class="custom-control-input" id="exampleSwitchInline3">
<label class="custom-control-label" for="exampleSwitchInline3">Disabled</label>
</div>
<div class="custom-control custom-switch custom-control-inline mr-4">
<input type="checkbox" disabled class="custom-control-input" id="exampleSwitchInline4">
<label class="custom-control-label" for="exampleSwitchInline4">Disabled</label>
</div>
</div>