Grand Ayatollah Naser Makarem Shirazi recently answered questions about the arrival of the Mahdi - the Hidden Imam who is the equivalent of the Messiah in Shi'ite Islam. Answering the question "When the Mahdi is revealed, will he arrive with a sword?" he explained at length how the Mahdi's arrival will be high-tech, as befits the modern age.
The following are excerpts from Shirazi's response: 
Naser Makarem Shirazi (Image: En.rasanews.ir)
"It was said by Imam Sadegh [the Sixth Shi'ite Imam, circa. 700-765 C.E.]: 'When our Lord arrives, the land will be illuminated by divine light, and [God's] creations will no longer require sunlight.' The interpretation of this saying is that the issue of light and energy is expressed in that both in daytime and nighttime powerful lights can replace sunlight.
"Should we see this as a miracle? Daily life should be conducted according to the ongoing laws of nature, and not according to miracles - because miracles are extraordinary and are for [times of] need and exceptional circumstances...
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"Another hadith states: With regards to [the Mahdi], God elevates low places and lowers high places, so that the entire world is visible to him like the palm of his hand...'
"Today we use satellites [and by means of them] cover extensive areas, so that anyone with a receiver can use them... In the time of the Mahdi's arrival, there will be a powerful apparatus, that may be difficult for us to imagine today, for transmitting images so that the entire world is visible like the palm of a hand. Without worldwide control by an intelligence [apparatus], there can be no unified global regime [as foretold that there will be when the Mahdi arrives], and no peace, security, and decency... Therefore, God grants him this tool... Once again I stress that this is a routine matter, and that it is inconceivable that it will come about based on a miracle; rather [it will come about] by means of ordinary tools that are based on scientific and industrial advances.
"Another hadith states: 'A bestial vessel is reserved for your Lord and Friend [the Mahdi]. What is the meaning of 'bestial vessel'? A cloud that is loud as thunder and fast as lightning, upon which he rides. Be aware that soon he will [appear] riding on clouds, and ascending to seven heavens and seven lands.' This does not refer to an ordinary cloud, as clouds are not vessels that can be sailed upon in outer space. [Clouds] travel near the atmosphere that is close to the earth, and they cannot attain great altitudes. Therefore, the meaning here is an extraordinary and very swift vessel that looks like a dense cloud in the sky; its sound is that of thunder and its power and speed is that of lightning. When it moves, it slashes the heart of the sky with extraordinary force, and in this way it can advance to any point in the firmament. Therefore, this is a super-modern vessel, and there is none like it today. It is like a spaceship and like other swift and amazing space vessels that are found [only] in stories today, but nobody knows how close [these vessels] come to truth and reality. Maybe it will be like [a spaceship] but in any case it is not a spaceship...
"When the Mahdi rules, the pure will have the height of freedom, and the criminals will be monitored - maybe so much so that sound waves will be detected from the walls of their houses, and when necessary it will be possible to understand what they say at home.
"Perhaps a century ago, this statement [about detecting sound waves] would have seemed like an unimaginable miracle. Yet today, some countries monitor traffic on the roads using radar, with no police present. Therefore, it is clear that during the global revolution of the Mahdi... there will be an unprecedented expansion of industry and technology."
 Fars (Iran), July 29, 2016.