Mobile marketing approaches through SMS has expanded rapidly in Europe and Asia as a new channel to reach the consumer. SMS initially received negative media coverage in many parts of Europe for being a new form of spam as some advertisers purchased lists and sent unsolicited content to consumer's phones; however, as guidelines are put in place by the mobile operators, SMS has become the most popular branch of the Mobile Marketing industry with several 100 million advertising SMS sent out every month in Europe alone. This is thanks in part to SMS messages being hardware agnostic - they can be delivered to practically any mobile phone, smartphone or feature phone and accessed without a Wi-Fi or mobile data connection. This is important to note since there are over 5 billion unique mobile phone subscribers worldwide in 2017, which is about 66% of the world population.
SMS marketing has both inbound and outbound marketing strategies. Inbound marketing focuses on lead generation, and outbound marketing focuses on sending messages for sales, promotions, contests, donations, television program voting, appointment and event reminders.
There are 5 key components to SMS marketing: sender ID, message size, content structure, spam compliance, and message delivery.

MMS mobile marketing can contain a timed slideshow of images, text, audio and video. This mobile content is delivered via MMS (Multimedia Message Service). Nearly all new phones produced with a color screen are capable of sending and receiving standard MMS message. Brands are able to both send (mobile terminated) and receive (mobile originated) rich content through MMS A2P (application-to-person) mobile networks to mobile subscribers. In some networks, brands are also able to sponsor messages that are sent P2P (person-to-person).
A typical MMS message based on the GSM encoding can have up to 1500 characters, whereas one based on Unicode can have up to 500 characters. Messages that are longer than the limit are truncated and not concatenated like an SMS.

Commonly referred to as GCM, Google Cloud Messaging served as C2DM's successor, making improvements to authentication and delivery, new API endpoints and messaging parameters, and the removal of limitations on API send-rates and message sizes. It is a message that pops up on a mobile device. It is the delivery of information from a software application to a computing device without any request from the client or the user. They look like SMS notifications but they are reached only the users who installed the app. The specifications vary for iOS and android users. SMS and push notifications can be part of a well-developed inbound mobile marketing strategy.
According to mobile marketing company Leanplum, Android sees open rates twice as high as those on iOS. Android sees open rates of 3.48 percent for push notification, versus iOS which has open rates