pleasant

agreeable

nice

enjoyable

warm

warmth

notification

notifies

notify

notifying

notice

notifier

notified

ui

user interface

operating system

os

announcer

announcing

announce

indicates

indicating

indication

sound effect

alert

dialog box

dialogue box

modal

event

software

computer

program

application

app sound

cellular phone

mobile device

mobile phone

smartphone

tablet

developers

development

cell phone

cellphone

multimedia

multi-media

synthesizer

electronic

synth