The romantic letters were for centuries one of the best ways to show love between two people.
Long and deep letters, handwritten and mailed, which could take months are testimony of passion, love and of course memorable, stormy among those who were not physically in the same place.
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However, in times of mobile phones and the Internet, these epistolary demonstrations have been replaced by applications that allow not only express love in words but also with pictures, shared lists, video calls and chat.
Be among those who have a long-distance relationship or between those who simply need tools to organize their day, in which each partner has endless obligations and plans.
So in BBC Technology we want to show what some apps that can be incorporated into married life in today's world are.
Image caption Wunderlist was considered one of the best applications for Mac in 2013.
In couples, especially in marriages, common activities are a priority.
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And that is essential coordination. Wunderlist is an application that stands out for its ability to rank the events of each day in separate lists, besides having a simple and fairly intuitive design.
There are social networks for everything: friends, relations, parents and of course, there are also designed for love. One is Couple.
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With one million users, it is a Couple social network that can accept only one person: your partner.
Image caption Couple With application can create a timeline of the events that marked the relationship.
It is ideal for sharing photos, exclusive chat, video calling directly to the person you have chosen to be your "other half" of this application. It also has a list of shared tasks.
In addition to offering privacy, another advantage of Couple is that it creates a timeline of the relationship that enables remember things that have been done during the days spent together.
The need for couples to organize reaches another dimension with the arrival of children. And Cozi is one of the most popular applications on the network for families with children and multiple obligations.
This app works on both mobile phones and personal computer and it can access all family members who are enrolled.
Image caption Cozi has been referenced by various means as one of the best applications for the family.
May be included by tasks, grocery list, outstanding issues for the day, traditional activities each week and major events scheduled in advance as birthdays and school calendar.
Cozi has become popular for its ability to store data and classify them by themes and colors.
There is also a space to fill a collection of anecdotes where you can record thoughts, complaints and even affectionate messages between family members.
Image caption Kindu has 600 questions about intimate affair in the couple.
No one can deny that sexual life is fundamental to good health of the couple. However, sometimes creativity can be lost in the routine and monotony.
Or at least that's what they thought the creators of Kindu, one of many applications that help couples to rediscover the path of passion through to find out about the fantasies of another or the more open discussion of taboo topics.
What makes the application is to collect the reactions of users to 600 intimate matters and manages to coordinate both members of the couple chosen as "definitely" or "open to discussion".
This lets you know what the other thinks about issues ranging from the most intimate to the tastes opinion against different sexual practices. Much to learn, in a list of 600 questions that perhaps had not considered before.
In general most couples dedicated applications are designed to share information: data, text messages, images, lists and created emoticons in the chat.
However, Avocado which includes everything above is an application that is designed to store this information on mobile devices of each of the lovers.
Image caption One possibility is that Avocado kissing the screen is automatically sent to the couple an animated picture.
Avocado's motto is "Together when we are separated" and, of course, goes further. Among its attractions, is one of its menu where you can send a "virtual" hug. When the other person receives it and put it close to the body, cell vibrates as if it really was your partner encircling arms.
The same applies when sending a kiss: one of the two kissing the screen and immediately sends an animated application to the other person through private chat image.