How did Uber company manage to market their service to both drivers/partners and users/riders through social media in the Middle East?

A lot of their work, which I am sure you have noticed, is done through their creative marketing campaigns. By partnering up with big events and offering discount codes for rides to the event, they get access to the user base of the event. The event will in turn also promote Uber's services in their marketing as an added value to their attendees. Uber have done a fantastic job of collaborating with events on win-win basis to where both parties cross-promote each other's services.

They addressed the market needs in their ads.And they were not limited to social media they have3rd party partners that made ads. on the papers like waseet and such requiring drivers and the benefits is very good for the drivers.for the riders it was the perfect conditions ads. , secure, safe, clean car, reasonable prices, and always on time.They implemented that idea as their unique branding once you recall Uber name you recall the experience you had which was very positive.

As the technology has changed and eve common people are using all kind of social networking. The adds on social media took an attention while they offered safe, secure and on time offers with clean and brand new cars at reasonable prices and people over here in Middle East is more in search of such kind of requirement due changing life styles definitely got attracted and once they started feeling the comfort, thru mouth publicity it started growing too..

Quite excellent feedback for the subject question from many experts. Few of my points are,

1) Uber not only collaborated for marketing and advertisement but also managed to do the same with service as well, which has not only helped in business but also sustain the business

2) With use of technology, Uber not only advertised well but also ensured delightful customer service which again resulted in a win-win situation both in marketing as well as in business

The marketing platform of Uber greatly focuses on social media sites, which is very different and unique from the traditional way. They are able to capture and understand the fast-paced life of the people here in the Middle East Countries. In just a few clicks of your fingers you could already book or get a cab or driver that would be available for you, unlike standing under the scourging heat of the sun and having tough competition with other commuters in order to get a cab, What Uber really offers is the convenience being just few clicks away and the comfort for the drivers and commuters. 

Let me tell you what happened in India which is one of the largest growing market for Uber. There was a huge overlapping in the TG where drivers and riders are. This is because many people in india bought commercial vehicles and hired drivers to run them. They understood the profit this service will bring them and took the opportunity. There were hyped stories where people left their good paying jobs and bought taxis and then multiplied them by hiring drivers. These are the same people who are active on social media and use taxi service more often than driving to save driving pressure in peak traffic and take benefit from low fare offers by service like uber. This is how even by advertising to drivers they got more customers and viseversa. 

As a customer what I need the best services with the less price if you compare the  quality of the Uber service timing customer service with price it's what people wish to have.... We are talking about matching demand with a Service in a market missing this! Plus what any company must do organized plan to achive.

Nothing changed in their communication strategy even if there are in Middle East, Europe or USA. Middle East is a glamour region where people have a lot of money and almost everybody have their own car. But this fact doesn't scared Uber and they were constant with their ads and vision. Of course they hired experts for their campaign who oversee the market but it s not a rocket science what they are doing. The business idea is what made it awesome. 

I think its important to note that in this region Careem was first to enter the market. Uber entered the market a couple of years later.

To answer your question, I would need to split my answer in two parts:

1- Users/Riders: As was pointed out a few times on this thread, Uber used launch events to highlight their services and use the events clients base to get more recognition. But also, it is important to note that they too have a "referral" system, where you get rewarded if you refer a friend.

2- Drivers/Partners: This was a lot easier to market, as most people would love to take on a second job to increase their monthly allowance, they just needed to be told or shown. Uber employees actually booked Careem cars for short trips and once they were in the car, they began the sales pitch and tried to attract more Careem drivers to also join their services.

Uber’s success stems not (just) from regulatory arbitrage or other malfeasance, but from having created a far more efficient market for car-hire services.Uber is sparking two major transformations of the car-hire sector. First, it is eliminating various transaction costs that have plagued the sector, particularly search costs, thereby creating something akin to a free market for car-hire services. Second, it is encouraging the vertical and horizontal integration of the sector, which is highly fragmented in many cities.Uber has basically eradicated search costs. Rather than calling a dispatcher and waiting, or standing on the street, users can hail a car from indoors and watch its progress toward their location. Watch On Bloom berg Misiek Piskorski a professor at Haward Business School, examine the $17 billion valuations for Uber, how they have grown their brand via social media and http://www.bloomberg.com/news/videos/b/2846c037-0ad9-4975-9c70-5938e40e4e65