These services will help you schedule your posts in social media: Hootsuite
Apart from social media management, Hootsuite offers blogging management, email campaigns management, marketing analytics, SEO analytics, ads management and many more options. The service offers a free plan that some might find interesting, but I see value in their Basic and higher plans. They cost from $200/mo and are billed annually, which can be a problem to small businesses. All in all this is a powerful platform that offers numerous features, post scheduling among them. It will be a valuable asset for bigger companies that can boast solid social networks presence and seek for an all-in-one inbound marketing tool. Postific
You can connect the following accounts with this service: Twitter, Facebook, LinkedIn, Pinterest, G+, Flickr, Tumblr. Postific is a massive inbound marketing tool, just like Hootsuite (although it lacks some features like ads management). No free trial is offered, but the service is designed for medium to large companies which are not as restricted in their marketing budget as startups. Social Pilot
The service works with the following networks: Facebook, Twitter, Instagram, G+, LinkedIn, Pinterest, Tumblr, Vkontakte, Xing. It has a mobile app that allows you to work on the go, which is nice. The list of networks is quite impressive, although scheduled posting is not available for Instagram, Vkontakte and Xing (due to their API policy). Social Pilot is a useful tool with very reasonable pricing. Companies of any size will enjoy the service and find it easy to use. No extra features, just post scheduling and social media performance analytics. SproutSocial
What accounts to connect: Twitter, Facebook, LinkedIn, Instagram, G+. The service offers a lot of features: analytics and reporting, social listening, automation and more. The pricing can be high for startups though (plans start from $99/mo per one user). 30-day free trial is a very nice bonus for those who decide to try tris platform. Buffer
Accounts you can connect: Facebook, Instagram, Twitter, LinkedIn, Pinterest, G+. Quite plain tool to schedule your tweets and posts. It cannot post to Instagram, but does grab notifications from there. The service has two plans - free and $10/mo. Any company can afford Buffer if it needs a simple scheduling tool without extras like analytics, campaign management and such. Friends + Me
The service connects to the following networks: G+, Facebook, Twitter, LinkedIn, Tumblr, Pinterest. Friends + Me tries to satisfy all user categories it seems, as apart from the web-site it offers a desktop software, a browser extension and a mobile app for your convenience. Overall the service is easy to implement, and it provides many pricing tiers that will fit any business size. 15-day free trial is a nice bonus to get a taste of Friends + Me. this tool, however, does not provide any additional features - only post scheduling.