isMobile & isTablet both return true

```
$agent->isMobile();
$agent->isTablet();
```

When we have tested this we have found that if the device user agent is iPad then when you call isMobile it is returning true and when you call isTablet is also returns true.

So when we do

```
if ($agent->isMobile()) {
return 'Mobile';
} elseif ($agent->isTablet()) {
return 'Tablet';
} elseif ($agent->isDesktop()) {
return 'Desktop';
}
```

if it's, for example, iPad or iPhone it will always return 'Mobile'.

Is this expected behaviour?