Product:

WordPress Slider Plugin

Question:

It isn't possible to have two different texts?

One that is long and works in "big screens" and one that works on phones etc?

Answer:

In your title, you can try to enter HTML code like following:

<span class="largescreen">This title is for large screen</span><span class="smallscreen">This title is for small screen</span>

Then in the plugin, step 3, Options tab, Advanced Options, enter the following text to the Custom CSS box:

.largescreen {
  display: block;
}
.smallscreen {
  display: none;
}

@media (max-width: 640px) {
  .largescreen {
    display: none;
  }
  .smallscreen {
    display: block;
  }
}

The above CSS code will hide the text of class largescreen and show the text of class smallscreen when the screen width is less than 640px.