It really boils down to what exactly you want to achieve at the end of a session. Yoga is all about developing your mind and body through physical movements and positions while meditation is about becoming one with yourself by relaxing and focusing on your inner core through visualisations and other techniques.
The question you should ask yourself is if you have the time to do both. If you do, then that is the best way forward. Because yoga and meditation go hand in hand. Most people who perform yoga tend to have a relaxing session post their yoga session by indulging in meditation. If you are going for overall wellbeing along with a sound body and mind, then yoga is what you need to try your hand in. But if you are someone who is trying refocusing their life and generally become more productive without breaking a sweat, then meditation is what you should be practising.
The one big difference is that yoga at times can be done in water, but meditation requires a hard surface where you can maintain posture. There are a lot of techniques in yoga that require a person to have perfect balance; practising in water makes sense because the buoyancy that you feel while in water helps with performing yoga. While on the other hand, it would be challenging to perform meditation while in water because the constant rocking can easily distract you.
Most people tend to feel easily distracted when they are in a crowd, and hence meditation is usually done alone but yoga, on the other hand, requires no such privacy, and you can often see many people performing yoga together.
Yoga to an extent requires a more spacious setting that meditation. As long as the environment is quiet and void of distraction, one can perform meditation but yoga cannot be done at the luxury of your workspace, it requires quite a bit of room to get some of the techniques correctly.
The other difference is that meditation requires absolute silence to do it correctly while yoga can be done even with music blaring on the side. It is all about being able to perform the techniques as per instructions and has nothing to do with distractions and noise.