Headspace is a good app. I rather liked it.
I've also grown up learning abt Hinduisim, it's philosophy , and practices. And that's where Meditation comes from.
Meditation has a very long history in India. It refers to a very specific spiritual practice. But when it was brought to the west, it became something of a tool to help ease daily life --Which I would argue is exactly what it was meant for anyway xD
There are many different types and not just the sort where you sit somewhere comfortable and try to clear your mind and let thoughts pass without judgement (In fact that's the hardest type for anyone who isn't practicing regularly).
I'm partial to breathing or Vipassana meditation; which is Buddhist. That's the one that just focused on your breathe.
Alternatively I like Japa or mantra meditation that uses a mala (108 strung beads...equivalent to a Catholic rosary).
Yoga as the west knows it (Technically called Hatha Yoga, there are three other types) is the method of calming and controlling body and breath to prepare for more sitting still meditation (in the traditional sense). But I think of some with focus and mindfulness, this sort of yoga can be meditation as well.
Then there's acting meditation. Because meditation is a process, not a state of mind-lessness you somehow reach and then regrettably have to leave to face the real world. If you do your actions with attention and Mind-Fullness, that can also serve as Meditation. And this is the sort I like best. It follows the principle of basic meditation whereby you have a single focus for your mind and dismiss all other thoughts.
In the end, if it helps you become more Self Aware, then any kind of practice that helps focus, calm, and slows down your thoughts is useful as Meditation in the non-Spiritual sense.