"[8] Songs of Innocence revisits the group members' youth in Ireland in the 1970s, touching on childhood memories, loves, and losses, while paying tribute to their musical inspirations.

The two previously collaborated in 2009 for the American theatre leg of Lady Gaga's Monster Ball Tour and in 2012 for Complicite's production of The Master and Margarita.

[17] Williams also invited Ric Lipson, Fisher's colleague at the design firm Stufish Entertainment Architects, based on positive experiences with him on past projects.

[16] The first production meeting between U2 and their creative team for the Innocence + Experience Tour was held in March 2013 in the South of France, over what Williams called a "mad weekend".

[15][18] During this first meeting, Williams, Devlin, and Lipson created a scrapbook that served as the "style guide" for the tour's presentation, consisting of cut-outs, drawings, and paintings.

The first is a lyric from the band's 1981 song "Rejoice" and represents the mindset of a teenage Bono feeling powerless to make a difference in a world plagued by the Troubles, who instead views personal psychological changes as a possibility; the second phrase represents the modern-day realisation that the same person could make a difference in the world through philanthropic efforts but still struggle with the complexities of internal change.

[19] "But the conceit here is to consistently merge the two stages, in a sense, and to engage the entire space visually, sonically and thematically, through the interplay of many other opposites extrapolated from the central one.

These include past and present, obscurity and fame, peace and war, audience and band, punk and statesman, grass-roots activism and corporate philanthropy, live action and animation.

[19] One such proposal was to have four "flying rooms" that would move around the arena and feature internal projections of the band members; the idea was instead re-imagined as the video imagery of a young Bono attempting to write a song in his bedroom.

[29] A flip-up piano was built into the B-stage,[30] with the lift designed to unfold the instrument 90 degrees like a book opening, rather than raise it directly upwards.

[21] The video screen was originally supposed to be 24 feet longer to match the length of the catwalk, but combined with the already-extensive weight of the other equipment, it would have made touring impractical.

[24] Due to the amount of space covered by the staging and the band members often being spread out, a traditional public address system front-loaded on one end of the arena was deemed inadequate.

The lighting of the main stage was meant to evoke a punk rock club from the late 1970s and early 1980s, a time and place that provided the thematic setting for the beginning of the Innocence + Experience shows.

Williams originally wanted to use actual fluorescent lights, but was convinced otherwise due to the risks of radio frequency (RF) interference that they posed.

[35] To archive uncompressed footage and access it on-demand during the shows' production, the tour staff used an EMC VNXe3200 portable flash storage unit worth about US$25,000.

With storage up to 6.6 petabytes and an hourly throughput of 13.4 TB, the Data Domain system could complete a nightly backup before the crew disassembled the stage.

[37] EMC's solution satisfied certain requirements dictated by the band, such as: mobility through a flight case form factor; expandable storage; and the capability to handle the large data loads from many cameras.

He suffered fractures of his shoulder blade, humerus, orbit, and pinky finger, requiring five hours of surgery at NewYork–Presbyterian Hospital/Weill Cornell Medical Center's Emergency Department.

[49] The injury forced the band to cancel a headlining appearance at KROQ Almost Acoustic Christmas,[50] as well as a week-long residency as the musical guest on The Tonight Show Starring Jimmy Fallon.

[52][53] On opening night, during the band's performance of the final song "I Still Haven't Found What I'm Looking For", guitarist the Edge fell off the stage catwalk while playing guitar and proceeding to the exit.

"[56] The group's 20 September 2015 show in Stockholm was postponed until later that week after an arena security breach that required police to evacuate the building and search for a suspect.

The rescheduling posed logistical challenges for the band, as the tour was supposed to end in Dublin more than a week prior to the new Paris dates, and crew members and equipment had been set to disperse.

[61] Writing about U2's plan to return to a Paris still on high alert, Don Kaplan of the New York Daily News said: "The Dublin band, born in the crucible of violence that gripped Ireland in the 1970s and '80s, has long collaborated with other musicians, artists, celebrities, and politicians to address issues concerning poverty, disease, and social injustice.

These songs were played underneath a single dangling light bulb, which was inspired by the decor of Bono's childhood bedroom and was intended as a metaphor for the intimacy and innocence of the band's early years.

[19] During the song's conclusion, the video screen displayed a light bulb smashing to release a tsunami that washed away the "innocence" of Cedarwood Road,[24] while pages from Ulysses, Lord of the Flies, the Psalms, and Alice in Wonderland fell from the venue ceiling like confetti.

For "Bullet the Blue Sky", the singer thematically re-interpreted the song, modifying the mid-song spoken passage to be a criticism of the modern-day Bono and his excesses by his younger self.

[78] During an off-day on 29 July, the Edge and Clayton made a surprise appearance at the 20th anniversary party for the band's fansite @u2, and they joined a U2 tribute act in performing "Where the Streets Have No Name" and "Out of Control".

[80] On 31 July, the final date of the North American leg of the tour, Bruce Springsteen accompanied the band for performances of "I Still Haven't Found What I'm Looking For" and "Stand By Me".

[83] Patti Smith joined U2 on two occasions to cover her song "People Have the Power"—in London on 29 October 2015,[84] and in Paris on 6 December 2015 for the first of the band's rescheduled dates in the city.

Philip Cosores of Consequence of Sound, reviewing a Los Angeles show, said, "U2 was every bit the brash, boisterous, larger-than-life rock stars fans would expect, or even hope for".