Modules for android buttons - doesn't handle scaling for you; you can add that

button.lua

local input = require("input")

local button = { }
button.__index = button

button.new = function(x, y, w, h)
  return setmetatable({ x = x, y = y, w = w, h = h}, button)
end

button.setTapCallback = function(self, callback, ...)
  if not self.heldID then
    if self.tapID then input.removeTapArea(self.tapID) end -- todo see input.regTapArea
    self.callback = callback
    self.tapID = input.regTapArea(self.x, self.y, self.w, self.h, callback, ...)
  else
    error("This is a held button already") -- could be dueled but for this example it's not
  end
  return self
end

button.setHeldCallback = function(self, startCallback, endCallback)
  if not self.tapID then
    if self.heldID then input.removeHeldArea(self.heldID) end -- todo see input.regHeldArea
    self.startCallback, self.endCallback = startCallback, endCallback
    self.heldID = input.regHeldArea(self.x, self.y, self.w, self.h, startCallback, endCallback)
  else
    error("This is a tap button already") -- could be dueled but for this example it's not
  end
  return self
end

button.draw = function(self)
  love.graphics.setColor(.4,.4,.4)
  love.graphics.rectangle("fill", self.x, self.y, self.w, self.h)
  love.graphics.setColor(1,1,1)
  if self.text then love.graphics.printf(self.text, self.x, self.y, self.w, "center") end
end

return button

input.lua

-- Handle input; singleton but could easily be tweaked so you can have multiple controllers per scene if you wanted to manage different scene inputs and pause others (e.g. a menu vs game)

local input = { 
  touches = { },
  tapDelay = 0.2,
  tapAreas = { }, -- see input.regTapArea
  heldAreas = { } -- see input.regHeldArea
}

local insert, remove = table.insert, table.remove

-- util func
local pointAABB = function(x1, y1, x2, y2, w, h)
  return x1 > x2 and x1 < x2 + w and
     y1 > y2 and y1 < y2 + h
end
--

input.getTouch = function(id)
  for k, v in ipairs(input.touches) do
    if v.id == id then return k, v end
  end
  return nil
end

input.touchpressed = function(id, x, y)
  insert(input.touches, {
      id = id,
      x = x, y = y,
      update = { },
      time = love.timer.getTime(),
      -- useful variables not internally used
      startX = x, startY = y,
    })
  for _, area in ipairs(input.heldAreas) do
    if pointAABB(x, y, area.x, area.y, area.w, area.h) then
      local id = #input.touches
      input.touches[id].held = area
      area.startCallback()
    end
  end
end

input.touchmoved = function(id, x, y)
  local key, touch = input.getTouch(id)
  if key then
    table.insert(touch.update, { x = x, y = y})
  end
end

input.touchreleased = function(id, x, y)
  local key, touch = input.getTouch(id)
  if key then
    local time = love.timer.getTime() - touch.time
    if touch.held then
      touch.held.endCallback()
    elseif time < input.tapDelay then -- if not touch.held
      input.tap(x, y)
    end
    remove(input.touches, key)
  end
end

input.tap = function(x, y)
  for _, area in ipairs(input.tapAreas) do
    if pointAABB(x, y, area.x, area.y, area.w, area.h) then
      if area.args then 
        area.callback(unpack(area.args))
      else area.callback() end
    end
  end
end

input.regTapArea = function(x, y, w, h, callback, ...)
  insert(input.tapAreas, {
      x = x, y = y, w = w, h = h, callback = callback,
    })
  local id = #input.tapAreas
  if select('#', ...) ~= 0 then
    input.tapAreas[id].args = {...}
  end
  
  return id -- todo add remove function using returned id
end

input.regHeldArea = function(x, y, w, h, startCallback, endCallback)
  insert(input.heldAreas, {
      x = x, y = y, w = w, h = h, startCallback = startCallback, endCallback = endCallback,
    })
  return #input.heldAreas -- todo add remove function using returned id
end

input.update = function() -- this function is like this cause I ripped it out of my old code where more things are done here (e.g. pinch zoom and drag movement)
  for _, touch in ipairs(input.touches) do
    for _, update in ipairs(touch.update) do
      touch.x, touch.y = update.x, update.y
    end
  end
end

return input

main.lua

local input = require("input")
local button = require("button")

local w, h = love.graphics.getDimensions()

local b1 = button.new(w/2-50, h/2-50 - 150, 100, 100)
b1:setTapCallback(function(button) button.text = "I've been tapped" end, b1) -- showing off args

local b2 = button.new(w/2-50, h/2-50 +   0, 100, 100)
b2:setHeldCallback(function() b2.text = "I'm being held" end, function() b2.text = nil end)

local b3 = button.new(w/2-50, h/2-50 + 150, 100, 100)
b3.text = "Reset"
b3:setTapCallback(function() b1.text = nil end)

love.update = function()
  input.update()
end

love.touchpressed = input.touchpressed -- lazy than writing a wrapper
love.touchmoved = input.touchmoved
love.touchreleased = input.touchrelease
-- debug on PC
love.mousepressed = function(x, y, _, _, isTouch)
  if ifTouch then return end
  input.touchpressed("mouse", x, y)
end
love.mousemoved = function(x, y, _, _, isTouch)
  if ifTouch then return end
  input.touchmoved("mouse", x, y)
end
love.mousereleased = function(x, y, _, _, isTouch)
  if ifTouch then return end
  input.touchreleased("mouse", x, y)
end

love.draw = function()
  b1:draw()
  b2:draw()
  b3:draw()
end