If you're seeking a relationship of 3+ months, Bumble (app) and eHarmony (website) are both good. On Bumble, women send the first message which saves time. You know they're interested before you write a message. On eHarmony, you have to fill out a 45-minute personality questionnaire and pay which weeds out people unlikely to meet.
Tinder seems to have the biggest pool. I ended up meeting someone I knew in-person my first day on it! But, you could literally write thoughtful messages and find only 1 in 3 reply. More work on your part.
